diff options
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/Kconfig | 13 | ||||
| -rw-r--r-- | drivers/spi/Makefile | 5 | ||||
| -rw-r--r-- | drivers/spi/spi-pxa2xx-dma.c | 392 | ||||
| -rw-r--r-- | drivers/spi/spi-pxa2xx-pxadma.c | 490 | ||||
| -rw-r--r-- | drivers/spi/spi-pxa2xx.c | 908 | ||||
| -rw-r--r-- | drivers/spi/spi-pxa2xx.h | 221 |
6 files changed, 1451 insertions, 578 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index a90393d7f106..e79884e997ae 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -297,9 +297,20 @@ config SPI_PPC4xx help This selects a driver for the PPC4xx SPI Controller. +config SPI_PXA2XX_PXADMA + bool "PXA2xx SSP legacy PXA DMA API support" + depends on SPI_PXA2XX && ARCH_PXA + help + Enable PXA private legacy DMA API support. Note that this is + deprecated in favor of generic DMA engine API. + +config SPI_PXA2XX_DMA + def_bool y + depends on SPI_PXA2XX && !SPI_PXA2XX_PXADMA + config SPI_PXA2XX tristate "PXA2xx SSP SPI master" - depends on ARCH_PXA || PCI + depends on ARCH_PXA || PCI || ACPI select PXA_SSP if ARCH_PXA help This enables using a PXA2xx or Sodaville SSP port as a SPI master diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 64e970ba261c..e53c30941340 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -47,7 +47,10 @@ obj-$(CONFIG_SPI_OMAP24XX) += spi-omap2-mcspi.o obj-$(CONFIG_SPI_ORION) += spi-orion.o obj-$(CONFIG_SPI_PL022) += spi-pl022.o obj-$(CONFIG_SPI_PPC4xx) += spi-ppc4xx.o -obj-$(CONFIG_SPI_PXA2XX) += spi-pxa2xx.o +spi-pxa2xx-platform-objs := spi-pxa2xx.o +spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_PXADMA) += spi-pxa2xx-pxadma.o +spi-pxa2xx-platform-$(CONFIG_SPI_PXA2XX_DMA) += spi-pxa2xx-dma.o +obj-$(CONFIG_SPI_PXA2XX) += spi-pxa2xx-platform.o obj-$(CONFIG_SPI_PXA2XX_PCI) += spi-pxa2xx-pci.o obj-$(CONFIG_SPI_RSPI) += spi-rspi.o obj-$(CONFIG_SPI_S3C24XX) += spi-s3c24xx-hw.o diff --git a/drivers/spi/spi-pxa2xx-dma.c b/drivers/spi/spi-pxa2xx-dma.c new file mode 100644 index 000000000000..c735c5a008a2 --- /dev/null +++ b/drivers/spi/spi-pxa2xx-dma.c @@ -0,0 +1,392 @@ +/* + * PXA2xx SPI DMA engine support. + * + * Copyright (C) 2013, Intel Corporation + * Author: Mika Westerberg <mika.westerberg@linux.intel.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/init.h> +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/pxa2xx_ssp.h> +#include <linux/scatterlist.h> +#include <linux/sizes.h> +#include <linux/spi/spi.h> +#include <linux/spi/pxa2xx_spi.h> + +#include "spi-pxa2xx.h" + +static int pxa2xx_spi_map_dma_buffer(struct driver_data *drv_data, + enum dma_data_direction dir) +{ + int i, nents, len = drv_data->len; + struct scatterlist *sg; + struct device *dmadev; + struct sg_table *sgt; + void *buf, *pbuf; + + /* + * Some DMA controllers have problems transferring buffers that are + * not multiple of 4 bytes. So we truncate the transfer so that it + * is suitable for such controllers, and handle the trailing bytes + * manually after the DMA completes. + * + * REVISIT: It would be better if this information could be + * retrieved directly from the DMA device in a similar way than + * ->copy_align etc. is done. + */ + len = ALIGN(drv_data->len, 4); + + if (dir == DMA_TO_DEVICE) { + dmadev = drv_data->tx_chan->device->dev; + sgt = &drv_data->tx_sgt; + buf = drv_data->tx; + drv_data->tx_map_len = len; + } else { + dmadev = drv_data->rx_chan->device->dev; + sgt = &drv_data->rx_sgt; + buf = drv_data->rx; + drv_data->rx_map_len = len; + } + + nents = DIV_ROUND_UP(len, SZ_2K); + if (nents != sgt->nents) { + int ret; + + sg_free_table(sgt); + ret = sg_alloc_table(sgt, nents, GFP_KERNEL); + if (ret) + return ret; + } + + pbuf = buf; + for_each_sg(sgt->sgl, sg, sgt->nents, i) { + size_t bytes = min_t(size_t, len, SZ_2K); + + if (buf) + sg_set_buf(sg, pbuf, bytes); + else + sg_set_buf(sg, drv_data->dummy, bytes); + + pbuf += bytes; + len -= bytes; + } + + nents = dma_map_sg(dmadev, sgt->sgl, sgt->nents, dir); + if (!nents) + return -ENOMEM; + + return nents; +} + +static void pxa2xx_spi_unmap_dma_buffer(struct driver_data *drv_data, + enum dma_data_direction dir) +{ + struct device *dmadev; + struct sg_table *sgt; + + if (dir == DMA_TO_DEVICE) { + dmadev = drv_data->tx_chan->device->dev; + sgt = &drv_data->tx_sgt; + } else { + dmadev = drv_data->rx_chan->device->dev; + sgt = &drv_data->rx_sgt; + } + + dma_unmap_sg(dmadev, sgt->sgl, sgt->nents, dir); +} + +static void pxa2xx_spi_unmap_dma_buffers(struct driver_data *drv_data) +{ + if (!drv_data->dma_mapped) + return; + + pxa2xx_spi_unmap_dma_buffer(drv_data, DMA_FROM_DEVICE); + pxa2xx_spi_unmap_dma_buffer(drv_data, DMA_TO_DEVICE); + + drv_data->dma_mapped = 0; +} + +static void pxa2xx_spi_dma_transfer_complete(struct driver_data *drv_data, + bool error) +{ + struct spi_message *msg = drv_data->cur_msg; + + /* + * It is possible that one CPU is handling ROR interrupt and other + * just gets DMA completion. Calling pump_transfers() twice for the + * same transfer leads to problems thus we prevent concurrent calls + * by using ->dma_running. + */ + if (atomic_dec_and_test(&drv_data->dma_running)) { + void __iomem *reg = drv_data->ioaddr; + + /* + * If the other CPU is still handling the ROR interrupt we + * might not know about the error yet. So we re-check the + * ROR bit here before we clear the status register. + */ + if (!error) { + u32 status = read_SSSR(reg) & drv_data->mask_sr; + error = status & SSSR_ROR; + } + + /* Clear status & disable interrupts */ + write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg); + write_SSSR_CS(drv_data, drv_data->clear_sr); + if (!pxa25x_ssp_comp(drv_data)) + write_SSTO(0, reg); + + if (!error) { + pxa2xx_spi_unmap_dma_buffers(drv_data); + + /* Handle the last bytes of unaligned transfer */ + drv_data->tx += drv_data->tx_map_len; + drv_data->write(drv_data); + + drv_data->rx += drv_data->rx_map_len; + drv_data->read(drv_data); + + msg->actual_length += drv_data->len; + msg->state = pxa2xx_spi_next_transfer(drv_data); + } else { + /* In case we got an error we disable the SSP now */ + write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg); + + msg->state = ERROR_STATE; + } + + tasklet_schedule(&drv_data->pump_transfers); + } +} + +static void pxa2xx_spi_dma_callback(void *data) +{ + pxa2xx_spi_dma_transfer_complete(data, false); +} + +static struct dma_async_tx_descriptor * +pxa2xx_spi_dma_prepare_one(struct driver_data *drv_data, + enum dma_transfer_direction dir) +{ + struct pxa2xx_spi_master *pdata = drv_data->master_info; + struct chip_data *chip = drv_data->cur_chip; + enum dma_slave_buswidth width; + struct dma_slave_config cfg; + struct dma_chan *chan; + struct sg_table *sgt; + int nents, ret; + + switch (drv_data->n_bytes) { + case 1: + width = DMA_SLAVE_BUSWIDTH_1_BYTE; + break; + case 2: + width = DMA_SLAVE_BUSWIDTH_2_BYTES; + break; + default: + width = DMA_SLAVE_BUSWIDTH_4_BYTES; + break; + } + + memset(&cfg, 0, sizeof(cfg)); + cfg.direction = dir; + + if (dir == DMA_MEM_TO_DEV) { + cfg.dst_addr = drv_data->ssdr_physical; + cfg.dst_addr_width = width; + cfg.dst_maxburst = chip->dma_burst_size; + cfg.slave_id = pdata->tx_slave_id; + + sgt = &drv_data->tx_sgt; + nents = drv_data->tx_nents; + chan = drv_data->tx_chan; + } else { + cfg.src_addr = drv_data->ssdr_physical; + cfg.src_addr_width = width; + cfg.src_maxburst = chip->dma_burst_size; + cfg.slave_id = pdata->rx_slave_id; + + sgt = &drv_data->rx_sgt; + nents = drv_data->rx_nents; + chan = drv_data->rx_chan; + } + + ret = dmaengine_slave_config(chan, &cfg); + if (ret) { + dev_warn(&drv_data->pdev->dev, "DMA slave config failed\n"); + return NULL; + } + + return dmaengine_prep_slave_sg(chan, sgt->sgl, nents, dir, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); +} + +static bool pxa2xx_spi_dma_filter(struct dma_chan *chan, void *param) +{ + const struct pxa2xx_spi_master *pdata = param; + + return chan->chan_id == pdata->tx_chan_id || + chan->chan_id == pdata->rx_chan_id; +} + +bool pxa2xx_spi_dma_is_possible(size_t len) +{ + return len <= MAX_DMA_LEN; +} + +int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data) +{ + const struct chip_data *chip = drv_data->cur_chip; + int ret; + + if (!chip->enable_dma) + return 0; + + /* Don't bother with DMA if we can't do even a single burst */ + if (drv_data->len < chip->dma_burst_size) + return 0; + + ret = pxa2xx_spi_map_dma_buffer(drv_data, DMA_TO_DEVICE); + if (ret <= 0) { + dev_warn(&drv_data->pdev->dev, "failed to DMA map TX\n"); + return 0; + } + + drv_data->tx_nents = ret; + + ret = pxa2xx_spi_map_dma_buffer(drv_data, DMA_FROM_DEVICE); + if (ret <= 0) { + pxa2xx_spi_unmap_dma_buffer(drv_data, DMA_TO_DEVICE); + dev_warn(&drv_data->pdev->dev, "failed to DMA map RX\n"); + return 0; + } + + drv_data->rx_nents = ret; + return 1; +} + +irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data) +{ + u32 status; + + status = read_SSSR(drv_data->ioaddr) & drv_data->mask_sr; + if (status & SSSR_ROR) { + dev_err(&drv_data->pdev->dev, "FIFO overrun\n"); + + dmaengine_terminate_all(drv_data->rx_chan); + dmaengine_terminate_all(drv_data->tx_chan); + + pxa2xx_spi_dma_transfer_complete(drv_data, true); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst) +{ + struct dma_async_tx_descriptor *tx_desc, *rx_desc; + + tx_desc = pxa2xx_spi_dma_prepare_one(drv_data, DMA_MEM_TO_DEV); + if (!tx_desc) { + dev_err(&drv_data->pdev->dev, + "failed to get DMA TX descriptor\n"); + return -EBUSY; + } + + rx_desc = pxa2xx_spi_dma_prepare_one(drv_data, DMA_DEV_TO_MEM); + if (!rx_desc) { + dev_err(&drv_data->pdev->dev, + "failed to get DMA RX descriptor\n"); + return -EBUSY; + } + + /* We are ready when RX completes */ + rx_desc->callback = pxa2xx_spi_dma_callback; + rx_desc->callback_param = drv_data; + + dmaengine_submit(rx_desc); + dmaengine_submit(tx_desc); + return 0; +} + +void pxa2xx_spi_dma_start(struct driver_data *drv_data) +{ + dma_async_issue_pending(drv_data->rx_chan); + dma_async_issue_pending(drv_data->tx_chan); + + atomic_set(&drv_data->dma_running, 1); +} + +int pxa2xx_spi_dma_setup(struct driver_data *drv_data) +{ + struct pxa2xx_spi_master *pdata = drv_data->master_info; + dma_cap_mask_t mask; + + dma_cap_zero(mask); + dma_cap_set(DMA_SLAVE, mask); + + drv_data->dummy = devm_kzalloc(&drv_data->pdev->dev, SZ_2K, GFP_KERNEL); + if (!drv_data->dummy) + return -ENOMEM; + + drv_data->tx_chan = dma_request_channel(mask, pxa2xx_spi_dma_filter, + pdata); + if (!drv_data->tx_chan) + return -ENODEV; + + drv_data->rx_chan = dma_request_channel(mask, pxa2xx_spi_dma_filter, + pdata); + if (!drv_data->rx_chan) { + dma_release_channel(drv_data->tx_chan); + drv_data->tx_chan = NULL; + return -ENODEV; + } + + return 0; +} + +void pxa2xx_spi_dma_release(struct driver_data *drv_data) +{ + if (drv_data->rx_chan) { + dmaengine_terminate_all(drv_data->rx_chan); + dma_release_channel(drv_data->rx_chan); + sg_free_table(&drv_data->rx_sgt); + drv_data->rx_chan = NULL; + } + if (drv_data->tx_chan) { + dmaengine_terminate_all(drv_data->tx_chan); + dma_release_channel(drv_data->tx_chan); + sg_free_table(&drv_data->tx_sgt); + drv_data->tx_chan = NULL; + } +} + +void pxa2xx_spi_dma_resume(struct driver_data *drv_data) +{ +} + +int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip, + struct spi_device *spi, + u8 bits_per_word, u32 *burst_code, + u32 *threshold) +{ + struct pxa2xx_spi_chip *chip_info = spi->controller_data; + + /* + * If the DMA burst size is given in chip_info we use that, + * otherwise we use the default. Also we use the default FIFO + * thresholds for now. + */ + *burst_code = chip_info ? chip_info->dma_burst_size : 16; + *threshold = SSCR1_RxTresh(RX_THRESH_DFLT) + | SSCR1_TxTresh(TX_THRESH_DFLT); + + return 0; +} diff --git a/drivers/spi/spi-pxa2xx-pxadma.c b/drivers/spi/spi-pxa2xx-pxadma.c new file mode 100644 index 000000000000..2916efc7cfe5 --- /dev/null +++ b/drivers/spi/spi-pxa2xx-pxadma.c @@ -0,0 +1,490 @@ +/* + * PXA2xx SPI private DMA support. + * + * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <linux/pxa2xx_ssp.h> +#include <linux/spi/spi.h> +#include <linux/spi/pxa2xx_spi.h> + +#include "spi-pxa2xx.h" + +#define DMA_INT_MASK (DCSR_ENDINTR | DCSR_STARTINTR | DCSR_BUSERR) +#define RESET_DMA_CHANNEL (DCSR_NODESC | DMA_INT_MASK) + +bool pxa2xx_spi_dma_is_possible(size_t len) +{ + /* Try to map dma buffer and do a dma transfer if successful, but + * only if the length is non-zero and less than MAX_DMA_LEN. + * + * Zero-length non-descriptor DMA is illegal on PXA2xx; force use + * of PIO instead. Care is needed above because the transfer may + * have have been passed with buffers that are already dma mapped. + * A zero-length transfer in PIO mode will not try to write/read + * to/from the buffers + * + * REVISIT large transfers are exactly where we most want to be + * using DMA. If this happens much, split those transfers into + * multiple DMA segments rather than forcing PIO. + */ + return len > 0 && len <= MAX_DMA_LEN; +} + +int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data) +{ + struct spi_message *msg = drv_data->cur_msg; + struct device *dev = &msg->spi->dev; + + if (!drv_data->cur_chip->enable_dma) + return 0; + + if (msg->is_dma_mapped) + return drv_data->rx_dma && drv_data->tx_dma; + + if (!IS_DMA_ALIGNED(drv_data->rx) || !IS_DMA_ALIGNED(drv_data->tx)) + return 0; + + /* Modify setup if rx buffer is null */ + if (drv_data->rx == NULL) { + *drv_data->null_dma_buf = 0; + drv_data->rx = drv_data->null_dma_buf; + drv_data->rx_map_len = 4; + } else + drv_data->rx_map_len = drv_data->len; + + + /* Modify setup if tx buffer is null */ + if (drv_data->tx == NULL) { + *drv_data->null_dma_buf = 0; + drv_data->tx = drv_data->null_dma_buf; + drv_data->tx_map_len = 4; + } else + drv_data->tx_map_len = drv_data->len; + + /* Stream map the tx buffer. Always do DMA_TO_DEVICE first + * so we flush the cache *before* invalidating it, in case + * the tx and rx buffers overlap. + */ + drv_data->tx_dma = dma_map_single(dev, drv_data->tx, + drv_data->tx_map_len, DMA_TO_DEVICE); + if (dma_mapping_error(dev, drv_data->tx_dma)) + return 0; + + /* Stream map the rx buffer */ + drv_data->rx_dma = dma_map_single(dev, drv_data->rx, + drv_data->rx_map_len, DMA_FROM_DEVICE); + if (dma_mapping_error(dev, drv_data->rx_dma)) { + dma_unmap_single(dev, drv_data->tx_dma, + drv_data->tx_map_len, DMA_TO_DEVICE); + return 0; + } + + return 1; +} + +static void pxa2xx_spi_unmap_dma_buffers(struct driver_data *drv_data) +{ + struct device *dev; + + if (!drv_data->dma_mapped) + return; + + if (!drv_data->cur_msg->is_dma_mapped) { + dev = &drv_data->cur_msg->spi->dev; + dma_unmap_single(dev, drv_data->rx_dma, + drv_data->rx_map_len, DMA_FROM_DEVICE); + dma_unmap_single(dev, drv_data->tx_dma, + drv_data->tx_map_len, DMA_TO_DEVICE); + } + + drv_data->dma_mapped = 0; +} + +static int wait_ssp_rx_stall(void const __iomem *ioaddr) +{ + unsigned long limit = loops_per_jiffy << 1; + + while ((read_SSSR(ioaddr) & SSSR_BSY) && --limit) + cpu_relax(); + + return limit; +} + +static int wait_dma_channel_stop(int channel) +{ + unsigned long limit = loops_per_jiffy << 1; + + while (!(DCSR(channel) & DCSR_STOPSTATE) && --limit) + cpu_relax(); + + return limit; +} + +static void pxa2xx_spi_dma_error_stop(struct driver_data *drv_data, + const char *msg) +{ + void __iomem *reg = drv_data->ioaddr; + + /* Stop and reset */ + DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL; + DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL; + write_SSSR_CS(drv_data, drv_data->clear_sr); + write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg); + if (!pxa25x_ssp_comp(drv_data)) + write_SSTO(0, reg); + pxa2xx_spi_flush(drv_data); + write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg); + + pxa2xx_spi_unmap_dma_buffers(drv_data); + + dev_err(&drv_data->pdev->dev, "%s\n", msg); + + drv_data->cur_msg->state = ERROR_STATE; + tasklet_schedule(&drv_data->pump_transfers); +} + +static void pxa2xx_spi_dma_transfer_complete(struct driver_data *drv_data) +{ + void __iomem *reg = drv_data->ioaddr; + struct spi_message *msg = drv_data->cur_msg; + + /* Clear and disable interrupts on SSP and DMA channels*/ + write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg); + write_SSSR_CS(drv_data, drv_data->clear_sr); + DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL; + DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL; + + if (wait_dma_channel_stop(drv_data->rx_channel) == 0) + dev_err(&drv_data->pdev->dev, + "dma_handler: dma rx channel stop failed\n"); + + if (wait_ssp_rx_stall(drv_data->ioaddr) == 0) + dev_err(&drv_data->pdev->dev, + "dma_transfer: ssp rx stall failed\n"); + + pxa2xx_spi_unmap_dma_buffers(drv_data); + + /* update the buffer pointer for the amount completed in dma */ + drv_data->rx += drv_data->len - + (DCMD(drv_data->rx_channel) & DCMD_LENGTH); + + /* read trailing data from fifo, it does not matter how many + * bytes are in the fifo just read until buffer is full + * or fifo is empty, which ever occurs first */ + drv_data->read(drv_data); + + /* return count of what was actually read */ + msg->actual_length += drv_data->len - + (drv_data->rx_end - drv_data->rx); + + /* Transfer delays and chip select release are + * handled in pump_transfers or giveback + */ + + /* Move to next transfer */ + msg->state = pxa2xx_spi_next_transfer(drv_data); + + /* Schedule transfer tasklet */ + tasklet_schedule(&drv_data->pump_transfers); +} + +void pxa2xx_spi_dma_handler(int channel, void *data) +{ + struct driver_data *drv_data = data; + u32 irq_status = DCSR(channel) & DMA_INT_MASK; + + if (irq_status & DCSR_BUSERR) { + + if (channel == drv_data->tx_channel) + pxa2xx_spi_dma_error_stop(drv_data, + "dma_handler: bad bus address on tx channel"); + else + pxa2xx_spi_dma_error_stop(drv_data, + "dma_handler: bad bus address on rx channel"); + return; + } + + /* PXA255x_SSP has no timeout interrupt, wait for tailing bytes */ + if ((channel == drv_data->tx_channel) + && (irq_status & DCSR_ENDINTR) + && (drv_data->ssp_type == PXA25x_SSP)) { + + /* Wait for rx to stall */ + if (wait_ssp_rx_stall(drv_data->ioaddr) == 0) + dev_err(&drv_data->pdev->dev, + "dma_handler: ssp rx stall failed\n"); + + /* finish this transfer, start the next */ + pxa2xx_spi_dma_transfer_complete(drv_data); + } +} + +irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data) +{ + u32 irq_status; + void __iomem *reg = drv_data->ioaddr; + + irq_status = read_SSSR(reg) & drv_data->mask_sr; + if (irq_status & SSSR_ROR) { + pxa2xx_spi_dma_error_stop(drv_data, + "dma_transfer: fifo overrun"); + return IRQ_HANDLED; + } + + /* Check for false positive timeout */ + if ((irq_status & SSSR_TINT) + && (DCSR(drv_data->tx_channel) & DCSR_RUN)) { + write_SSSR(SSSR_TINT, reg); + return IRQ_HANDLED; + } + + if (irq_status & SSSR_TINT || drv_data->rx == drv_data->rx_end) { + + /* Clear and disable timeout interrupt, do the rest in + * dma_transfer_complete */ + if (!pxa25x_ssp_comp(drv_data)) + write_SSTO(0, reg); + + /* finish this transfer, start the next */ + pxa2xx_spi_dma_transfer_complete(drv_data); + + return IRQ_HANDLED; + } + + /* Opps problem detected */ + return IRQ_NONE; +} + +int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst) +{ + u32 dma_width; + + switch (drv_data->n_bytes) { + case 1: + dma_width = DCMD_WIDTH1; + break; + case 2: + dma_width = DCMD_WIDTH2; + break; + default: + dma_width = DCMD_WIDTH4; + break; + } + + /* Setup rx DMA Channel */ + DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL; + DSADR(drv_data->rx_channel) = drv_data->ssdr_physical; + DTADR(drv_data->rx_channel) = drv_data->rx_dma; + if (drv_data->rx == drv_data->null_dma_buf) + /* No target address increment */ + DCMD(drv_data->rx_channel) = DCMD_FLOWSRC + | dma_width + | dma_burst + | drv_data->len; + else + DCMD(drv_data->rx_channel) = DCMD_INCTRGADDR + | DCMD_FLOWSRC + | dma_width + | dma_burst + | drv_data->len; + + /* Setup tx DMA Channel */ + DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL; + DSADR(drv_data->tx_channel) = drv_data->tx_dma; + DTADR(drv_data->tx_channel) = drv_data->ssdr_physical; + if (drv_data->tx == drv_data->null_dma_buf) + /* No source address increment */ + DCMD(drv_data->tx_channel) = DCMD_FLOWTRG + | dma_width + | dma_burst + | drv_data->len; + else + DCMD(drv_data->tx_channel) = DCMD_INCSRCADDR + | DCMD_FLOWTRG + | dma_width + | dma_burst + | drv_data->len; + + /* Enable dma end irqs on SSP to detect end of transfer */ + if (drv_data->ssp_type == PXA25x_SSP) + DCMD(drv_data->tx_channel) |= DCMD_ENDIRQEN; + + return 0; +} + +void pxa2xx_spi_dma_start(struct driver_data *drv_data) +{ + DCSR(drv_data->rx_channel) |= DCSR_RUN; + DCSR(drv_data->tx_channel) |= DCSR_RUN; +} + +int pxa2xx_spi_dma_setup(struct driver_data *drv_data) +{ + struct device *dev = &drv_data->pdev->dev; + struct ssp_device *ssp = drv_data->ssp; + + /* Get two DMA channels (rx and tx) */ + drv_data->rx_channel = pxa_request_dma("pxa2xx_spi_ssp_rx", + DMA_PRIO_HIGH, + pxa2xx_spi_dma_handler, + drv_data); + if (drv_data->rx_channel < 0) { + dev_err(dev, "problem (%d) requesting rx channel\n", + drv_data->rx_channel); + return -ENODEV; + } + drv_data->tx_channel = pxa_request_dma("pxa2xx_spi_ssp_tx", + DMA_PRIO_MEDIUM, + pxa2xx_spi_dma_handler, + drv_data); + if (drv_data->tx_channel < 0) { + dev_err(dev, "problem (%d) requesting tx channel\n", + drv_data->tx_channel); + pxa_free_dma(drv_data->rx_channel); + return -ENODEV; + } + + DRCMR(ssp->drcmr_rx) = DRCMR_MAPVLD | drv_data->rx_channel; + DRCMR(ssp->drcmr_tx) = DRCMR_MAPVLD | drv_data->tx_channel; + + return 0; +} + +void pxa2xx_spi_dma_release(struct driver_data *drv_data) +{ + struct ssp_device *ssp = drv_data->ssp; + + DRCMR(ssp->drcmr_rx) = 0; + DRCMR(ssp->drcmr_tx) = 0; + + if (drv_data->tx_channel != 0) + pxa_free_dma(drv_data->tx_channel); + if (drv_data->rx_channel != 0) + pxa_free_dma(drv_data->rx_channel); +} + +void pxa2xx_spi_dma_resume(struct driver_data *drv_data) +{ + if (drv_data->rx_channel != -1) + DRCMR(drv_data->ssp->drcmr_rx) = + DRCMR_MAPVLD | drv_data->rx_channel; + if (drv_data->tx_channel != -1) + DRCMR(drv_data->ssp->drcmr_tx) = + DRCMR_MAPVLD | drv_data->tx_channel; +} + +int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip, + struct spi_device *spi, + u8 bits_per_word, u32 *burst_code, + u32 *threshold) +{ + struct pxa2xx_spi_chip *chip_info = + (struct pxa2xx_spi_chip *)spi->controller_data; + int bytes_per_word; + int burst_bytes; + int thresh_words; + int req_burst_size; + int retval = 0; + + /* Set the threshold (in registers) to equal the same amount of data + * as represented by burst size (in bytes). The computation below + * is (burst_size rounded up to nearest 8 byte, word or long word) + * divided by (bytes/register); the tx threshold is the inverse of + * the rx, so that there will always be enough data in the rx fifo + * to satisfy a burst, and there will always be enough space in the + * tx fifo to accept a burst (a tx burst will overwrite the fifo if + * there is not enough space), there must always remain enough empty + * space in the rx fifo for any data loaded to the tx fifo. + * Whenever burst_size (in bytes) equals bits/word, the fifo threshold + * will be 8, or half the fifo; + * The threshold can only be set to 2, 4 or 8, but not 16, because + * to burst 16 to the tx fifo, the fifo would have to be empty; + * however, the minimum fifo trigger level is 1, and the tx will + * request service when the fifo is at this level, with only 15 spaces. + */ + + /* find bytes/word */ + if (bits_per_word <= 8) + bytes_per_word = 1; + else if (bits_per_word <= 16) + bytes_per_word = 2; + else + bytes_per_word = 4; + + /* use struct pxa2xx_spi_chip->dma_burst_size if available */ + if (chip_info) + req_burst_size = chip_info->dma_burst_size; + else { + switch (chip->dma_burst_size) { + default: + /* if the default burst size is not set, + * do it now */ + chip->dma_burst_size = DCMD_BURST8; + case DCMD_BURST8: + req_burst_size = 8; + break; + case DCMD_BURST16: + req_burst_size = 16; + break; + case DCMD_BURST32: + req_burst_size = 32; + break; + } + } + if (req_burst_size <= 8) { + *burst_code = DCMD_BURST8; + burst_bytes = 8; + } else if (req_burst_size <= 16) { + if (bytes_per_word == 1) { + /* don't burst more than 1/2 the fifo */ + *burst_code = DCMD_BURST8; + burst_bytes = 8; + retval = 1; + } else { + *burst_code = DCMD_BURST16; + burst_bytes = 16; + } + } else { + if (bytes_per_word == 1) { + /* don't burst more than 1/2 the fifo */ + *burst_code = DCMD_BURST8; + burst_bytes = 8; + retval = 1; + } else if (bytes_per_word == 2) { + /* don't burst more than 1/2 the fifo */ + *burst_code = DCMD_BURST16; + burst_bytes = 16; + retval = 1; + } else { + *burst_code = DCMD_BURST32; + burst_bytes = 32; + } + } + + thresh_words = burst_bytes / bytes_per_word; + + /* thresh_words will be between 2 and 8 */ + *threshold = (SSCR1_RxTresh(thresh_words) & SSCR1_RFT) + | (SSCR1_TxTresh(16-thresh_words) & SSCR1_TFT); + + return retval; +} diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c index 304cf6eb50e6..90b27a3508a6 100644 --- a/drivers/spi/spi-pxa2xx.c +++ b/drivers/spi/spi-pxa2xx.c @@ -1,5 +1,6 @@ /* * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs + * Copyright (C) 2013, Intel Corporation * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -24,18 +25,20 @@ #include <linux/interrupt.h> #include <linux/platform_device.h> #include <linux/spi/pxa2xx_spi.h> -#include <linux/dma-mapping.h> #include <linux/spi/spi.h> #include <linux/workqueue.h> #include <linux/delay.h> #include <linux/gpio.h> #include <linux/slab.h> #include <linux/clk.h> +#include <linux/pm_runtime.h> +#include <linux/acpi.h> #include <asm/io.h> #include <asm/irq.h> #include <asm/delay.h> +#include "spi-pxa2xx.h" MODULE_AUTHOR("Stephen Street"); MODULE_DESCRIPTION("PXA2xx SSP SPI Controller"); @@ -46,12 +49,6 @@ MODULE_ALIAS("platform:pxa2xx-spi"); #define TIMOUT_DFLT 1000 -#define DMA_INT_MASK (DCSR_ENDINTR | DCSR_STARTINTR | DCSR_BUSERR) -#define RESET_DMA_CHANNEL (DCSR_NODESC | DMA_INT_MASK) -#define IS_DMA_ALIGNED(x) IS_ALIGNED((unsigned long)(x), DMA_ALIGNMENT) -#define MAX_DMA_LEN 8191 -#define DMA_ALIGNMENT 8 - /* * for testing SSCR1 changes that require SSP restart, basically * everything except the service and interrupt enables, the pxa270 developer @@ -66,105 +63,97 @@ MODULE_ALIAS("platform:pxa2xx-spi"); | SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \ | SSCR1_SPH | SSCR1_SPO | SSCR1_LBM) -#define DEFINE_SSP_REG(reg, off) \ -static inline u32 read_##reg(void const __iomem *p) \ -{ return __raw_readl(p + (off)); } \ -\ -static inline void write_##reg(u32 v, void __iomem *p) \ -{ __raw_writel(v, p + (off)); } - -DEFINE_SSP_REG(SSCR0, 0x00) -DEFINE_SSP_REG(SSCR1, 0x04) -DEFINE_SSP_REG(SSSR, 0x08) -DEFINE_SSP_REG(SSITR, 0x0c) -DEFINE_SSP_REG(SSDR, 0x10) -DEFINE_SSP_REG(SSTO, 0x28) -DEFINE_SSP_REG(SSPSP, 0x2c) - -#define START_STATE ((void*)0) -#define RUNNING_STATE ((void*)1) -#define DONE_STATE ((void*)2) -#define ERROR_STATE ((void*)-1) - -struct driver_data { - /* Driver model hookup */ - struct platform_device *pdev; - - /* SSP Info */ - struct ssp_device *ssp; +#define LPSS_RX_THRESH_DFLT 64 +#define LPSS_TX_LOTHRESH_DFLT 160 +#define LPSS_TX_HITHRESH_DFLT 224 - /* SPI framework hookup */ - enum pxa_ssp_type ssp_type; - struct spi_master *master; +/* Offset from drv_data->lpss_base */ +#define SPI_CS_CONTROL 0x18 +#define SPI_CS_CONTROL_SW_MODE BIT(0) +#define SPI_CS_CONTROL_CS_HIGH BIT(1) - /* PXA hookup */ - struct pxa2xx_spi_master *master_info; - - /* DMA setup stuff */ - int rx_channel; - int tx_channel; - u32 *null_dma_buf; - - /* SSP register addresses */ - void __iomem *ioaddr; - u32 ssdr_physical; - - /* SSP masks*/ - u32 dma_cr1; - u32 int_cr1; - u32 clear_sr; - u32 mask_sr; - - /* Maximun clock rate */ - unsigned long max_clk_rate; - - /* Message Transfer pump */ - struct tasklet_struct pump_transfers; - - /* Current message transfer state info */ - struct spi_message* cur_msg; - struct spi_transfer* cur_transfer; - struct chip_data *cur_chip; - size_t len; - void *tx; - void *tx_end; - void *rx; - void *rx_end; - int dma_mapped; - dma_addr_t rx_dma; - dma_addr_t tx_dma; - size_t rx_map_len; - size_t tx_map_len; - u8 n_bytes; - u32 dma_width; - int (*write)(struct driver_data *drv_data); - int (*read)(struct driver_data *drv_data); - irqreturn_t (*transfer_handler)(struct driver_data *drv_data); - void (*cs_control)(u32 command); -}; +static bool is_lpss_ssp(const struct driver_data *drv_data) +{ + return drv_data->ssp_type == LPSS_SSP; +} -struct chip_data { - u32 cr0; - u32 cr1; - u32 psp; - u32 timeout; - u8 n_bytes; - u32 dma_width; - u32 dma_burst_size; - u32 threshold; - u32 dma_threshold; - u8 enable_dma; - u8 bits_per_word; - u32 speed_hz; - union { - int gpio_cs; - unsigned int frm; - }; - int gpio_cs_inverted; - int (*write)(struct driver_data *drv_data); - int (*read)(struct driver_data *drv_data); - void (*cs_control)(u32 command); -}; +/* + * Read and write LPSS SSP private registers. Caller must first check that + * is_lpss_ssp() returns true before these can be called. + */ +static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset) +{ + WARN_ON(!drv_data->lpss_base); + return readl(drv_data->lpss_base + offset); +} + +static void __lpss_ssp_write_priv(struct driver_data *drv_data, + unsigned offset, u32 value) +{ + WARN_ON(!drv_data->lpss_base); + writel(value, drv_data->lpss_base + offset); +} + +/* + * lpss_ssp_setup - perform LPSS SSP specific setup + * @drv_data: pointer to the driver private data + * + * Perform LPSS SSP specific setup. This function must be called first if + * one is going to use LPSS SSP private registers. + */ +static void lpss_ssp_setup(struct driver_data *drv_data) +{ + unsigned offset = 0x400; + u32 value, orig; + + if (!is_lpss_ssp(drv_data)) + return; + + /* + * Perform auto-detection of the LPSS SSP private registers. They + * can be either at 1k or 2k offset from the base address. + */ + orig = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL); + + value = orig | SPI_CS_CONTROL_SW_MODE; + writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL); + value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL); + if (value != (orig | SPI_CS_CONTROL_SW_MODE)) { + offset = 0x800; + goto detection_done; + } + + value &= ~SPI_CS_CONTROL_SW_MODE; + writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL); + value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL); + if (value != orig) { + offset = 0x800; + goto detection_done; + } + +detection_done: + /* Now set the LPSS base */ + drv_data->lpss_base = drv_data->ioaddr + offset; + + /* Enable software chip select control */ + value = SPI_CS_CONTROL_SW_MODE | SPI_CS_CONTROL_CS_HIGH; + __lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value); +} + +static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable) +{ + u32 value; + + if (!is_lpss_ssp(drv_data)) + return; + + value = __lpss_ssp_read_priv(drv_data, SPI_CS_CONTROL); + if (enable) + value &= ~SPI_CS_CONTROL_CS_HIGH; + else + value |= SPI_CS_CONTROL_CS_HIGH; + __lpss_ssp_write_priv(drv_data, SPI_CS_CONTROL, value); +} static void cs_assert(struct driver_data *drv_data) { @@ -180,8 +169,12 @@ static void cs_assert(struct driver_data *drv_data) return; } - if (gpio_is_valid(chip->gpio_cs)) + if (gpio_is_valid(chip->gpio_cs)) { gpio_set_value(chip->gpio_cs, chip->gpio_cs_inverted); + return; + } + + lpss_ssp_cs_control(drv_data, true); } static void cs_deassert(struct driver_data *drv_data) @@ -196,30 +189,15 @@ static void cs_deassert(struct driver_data *drv_data) return; } - if (gpio_is_valid(chip->gpio_cs)) + if (gpio_is_valid(chip->gpio_cs)) { gpio_set_value(chip->gpio_cs, !chip->gpio_cs_inverted); -} - -static void write_SSSR_CS(struct driver_data *drv_data, u32 val) -{ - void __iomem *reg = drv_data->ioaddr; - - if (drv_data->ssp_type == CE4100_SSP) - val |= read_SSSR(reg) & SSSR_ALT_FRM_MASK; - - write_SSSR(val, reg); -} + return; + } -static int pxa25x_ssp_comp(struct driver_data *drv_data) -{ - if (drv_data->ssp_type == PXA25x_SSP) - return 1; - if (drv_data->ssp_type == CE4100_SSP) - return 1; - return 0; + lpss_ssp_cs_control(drv_data, false); } -static int flush(struct driver_data *drv_data) +int pxa2xx_spi_flush(struct driver_data *drv_data) { unsigned long limit = loops_per_jiffy << 1; @@ -345,7 +323,7 @@ static int u32_reader(struct driver_data *drv_data) return drv_data->rx == drv_data->rx_end; } -static void *next_transfer(struct driver_data *drv_data) +void *pxa2xx_spi_next_transfer(struct driver_data *drv_data) { struct spi_message *msg = drv_data->cur_msg; struct spi_transfer *trans = drv_data->cur_transfer; @@ -361,76 +339,6 @@ static void *next_transfer(struct driver_data *drv_data) return DONE_STATE; } -static int map_dma_buffers(struct driver_data *drv_data) -{ - struct spi_message *msg = drv_data->cur_msg; - struct device *dev = &msg->spi->dev; - - if (!drv_data->cur_chip->enable_dma) - return 0; - - if (msg->is_dma_mapped) - return drv_data->rx_dma && drv_data->tx_dma; - - if (!IS_DMA_ALIGNED(drv_data->rx) || !IS_DMA_ALIGNED(drv_data->tx)) - return 0; - - /* Modify setup if rx buffer is null */ - if (drv_data->rx == NULL) { - *drv_data->null_dma_buf = 0; - drv_data->rx = drv_data->null_dma_buf; - drv_data->rx_map_len = 4; - } else - drv_data->rx_map_len = drv_data->len; - - - /* Modify setup if tx buffer is null */ - if (drv_data->tx == NULL) { - *drv_data->null_dma_buf = 0; - drv_data->tx = drv_data->null_dma_buf; - drv_data->tx_map_len = 4; - } else - drv_data->tx_map_len = drv_data->len; - - /* Stream map the tx buffer. Always do DMA_TO_DEVICE first - * so we flush the cache *before* invalidating it, in case - * the tx and rx buffers overlap. - */ - drv_data->tx_dma = dma_map_single(dev, drv_data->tx, - drv_data->tx_map_len, DMA_TO_DEVICE); - if (dma_mapping_error(dev, drv_data->tx_dma)) - return 0; - - /* Stream map the rx buffer */ - drv_data->rx_dma = dma_map_single(dev, drv_data->rx, - drv_data->rx_map_len, DMA_FROM_DEVICE); - if (dma_mapping_error(dev, drv_data->rx_dma)) { - dma_unmap_single(dev, drv_data->tx_dma, - drv_data->tx_map_len, DMA_TO_DEVICE); - return 0; - } - - return 1; -} - -static void unmap_dma_buffers(struct driver_data *drv_data) -{ - struct device *dev; - - if (!drv_data->dma_mapped) - return; - - if (!drv_data->cur_msg->is_dma_mapped) { - dev = &drv_data->cur_msg->spi->dev; - dma_unmap_single(dev, drv_data->rx_dma, - drv_data->rx_map_len, DMA_FROM_DEVICE); - dma_unmap_single(dev, drv_data->tx_dma, - drv_data->tx_map_len, DMA_TO_DEVICE); - } - - drv_data->dma_mapped = 0; -} - /* caller already set message->status; dma and pio irqs are blocked */ static void giveback(struct driver_data *drv_data) { @@ -483,161 +391,6 @@ static void giveback(struct driver_data *drv_data) drv_data->cur_chip = NULL; } -static int wait_ssp_rx_stall(void const __iomem *ioaddr) -{ - unsigned long limit = loops_per_jiffy << 1; - - while ((read_SSSR(ioaddr) & SSSR_BSY) && --limit) - cpu_relax(); - - return limit; -} - -static int wait_dma_channel_stop(int channel) -{ - unsigned long limit = loops_per_jiffy << 1; - - while (!(DCSR(channel) & DCSR_STOPSTATE) && --limit) - cpu_relax(); - - return limit; -} - -static void dma_error_stop(struct driver_data *drv_data, const char *msg) -{ - void __iomem *reg = drv_data->ioaddr; - - /* Stop and reset */ - DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL; - DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL; - write_SSSR_CS(drv_data, drv_data->clear_sr); - write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg); - if (!pxa25x_ssp_comp(drv_data)) - write_SSTO(0, reg); - flush(drv_data); - write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg); - - unmap_dma_buffers(drv_data); - - dev_err(&drv_data->pdev->dev, "%s\n", msg); - - drv_data->cur_msg->state = ERROR_STATE; - tasklet_schedule(&drv_data->pump_transfers); -} - -static void dma_transfer_complete(struct driver_data *drv_data) -{ - void __iomem *reg = drv_data->ioaddr; - struct spi_message *msg = drv_data->cur_msg; - - /* Clear and disable interrupts on SSP and DMA channels*/ - write_SSCR1(read_SSCR1(reg) & ~drv_data->dma_cr1, reg); - write_SSSR_CS(drv_data, drv_data->clear_sr); - DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL; - DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL; - - if (wait_dma_channel_stop(drv_data->rx_channel) == 0) - dev_err(&drv_data->pdev->dev, - "dma_handler: dma rx channel stop failed\n"); - - if (wait_ssp_rx_stall(drv_data->ioaddr) == 0) - dev_err(&drv_data->pdev->dev, - "dma_transfer: ssp rx stall failed\n"); - - unmap_dma_buffers(drv_data); - - /* update the buffer pointer for the amount completed in dma */ - drv_data->rx += drv_data->len - - (DCMD(drv_data->rx_channel) & DCMD_LENGTH); - - /* read trailing data from fifo, it does not matter how many - * bytes are in the fifo just read until buffer is full - * or fifo is empty, which ever occurs first */ - drv_data->read(drv_data); - - /* return count of what was actually read */ - msg->actual_length += drv_data->len - - (drv_data->rx_end - drv_data->rx); - - /* Transfer delays and chip select release are - * handled in pump_transfers or giveback - */ - - /* Move to next transfer */ - msg->state = next_transfer(drv_data); - - /* Schedule transfer tasklet */ - tasklet_schedule(&drv_data->pump_transfers); -} - -static void dma_handler(int channel, void *data) -{ - struct driver_data *drv_data = data; - u32 irq_status = DCSR(channel) & DMA_INT_MASK; - - if (irq_status & DCSR_BUSERR) { - - if (channel == drv_data->tx_channel) - dma_error_stop(drv_data, - "dma_handler: " - "bad bus address on tx channel"); - else - dma_error_stop(drv_data, - "dma_handler: " - "bad bus address on rx channel"); - return; - } - - /* PXA255x_SSP has no timeout interrupt, wait for tailing bytes */ - if ((channel == drv_data->tx_channel) - && (irq_status & DCSR_ENDINTR) - && (drv_data->ssp_type == PXA25x_SSP)) { - - /* Wait for rx to stall */ - if (wait_ssp_rx_stall(drv_data->ioaddr) == 0) - dev_err(&drv_data->pdev->dev, - "dma_handler: ssp rx stall failed\n"); - - /* finish this transfer, start the next */ - dma_transfer_complete(drv_data); - } -} - -static irqreturn_t dma_transfer(struct driver_data *drv_data) -{ - u32 irq_status; - void __iomem *reg = drv_data->ioaddr; - - irq_status = read_SSSR(reg) & drv_data->mask_sr; - if (irq_status & SSSR_ROR) { - dma_error_stop(drv_data, "dma_transfer: fifo overrun"); - return IRQ_HANDLED; - } - - /* Check for false positive timeout */ - if ((irq_status & SSSR_TINT) - && (DCSR(drv_data->tx_channel) & DCSR_RUN)) { - write_SSSR(SSSR_TINT, reg); - return IRQ_HANDLED; - } - - if (irq_status & SSSR_TINT || drv_data->rx == drv_data->rx_end) { - - /* Clear and disable timeout interrupt, do the rest in - * dma_transfer_complete */ - if (!pxa25x_ssp_comp(drv_data)) - write_SSTO(0, reg); - - /* finish this transfer, start the next */ - dma_transfer_complete(drv_data); - - return IRQ_HANDLED; - } - - /* Opps problem detected */ - return IRQ_NONE; -} - static void reset_sccr1(struct driver_data *drv_data) { void __iomem *reg = drv_data->ioaddr; @@ -659,7 +412,7 @@ static void int_error_stop(struct driver_data *drv_data, const char* msg) reset_sccr1(drv_data); if (!pxa25x_ssp_comp(drv_data)) write_SSTO(0, reg); - flush(drv_data); + pxa2xx_spi_flush(drv_data); write_SSCR0(read_SSCR0(reg) & ~SSCR0_SSE, reg); dev_err(&drv_data->pdev->dev, "%s\n", msg); @@ -687,7 +440,7 @@ static void int_transfer_complete(struct driver_data *drv_data) */ /* Move to next transfer */ - drv_data->cur_msg->state = next_transfer(drv_data); + drv_data->cur_msg->state = pxa2xx_spi_next_transfer(drv_data); /* Schedule transfer tasklet */ tasklet_schedule(&drv_data->pump_transfers); @@ -767,10 +520,20 @@ static irqreturn_t ssp_int(int irq, void *dev_id) { struct driver_data *drv_data = dev_id; void __iomem *reg = drv_data->ioaddr; - u32 sccr1_reg = read_SSCR1(reg); + u32 sccr1_reg; u32 mask = drv_data->mask_sr; u32 status; + /* + * The IRQ might be shared with other peripherals so we must first + * check that are we RPM suspended or not. If we are we assume that + * the IRQ was not for us (we shouldn't be RPM suspended when the + * interrupt is enabled). + */ + if (pm_runtime_suspended(&drv_data->pdev->dev)) + return IRQ_NONE; + + sccr1_reg = read_SSCR1(reg); status = read_SSSR(reg); /* Ignore possible writes if we don't need to write */ @@ -798,103 +561,6 @@ static irqreturn_t ssp_int(int irq, void *dev_id) return drv_data->transfer_handler(drv_data); } -static int set_dma_burst_and_threshold(struct chip_data *chip, - struct spi_device *spi, - u8 bits_per_word, u32 *burst_code, - u32 *threshold) -{ - struct pxa2xx_spi_chip *chip_info = - (struct pxa2xx_spi_chip *)spi->controller_data; - int bytes_per_word; - int burst_bytes; - int thresh_words; - int req_burst_size; - int retval = 0; - - /* Set the threshold (in registers) to equal the same amount of data - * as represented by burst size (in bytes). The computation below - * is (burst_size rounded up to nearest 8 byte, word or long word) - * divided by (bytes/register); the tx threshold is the inverse of - * the rx, so that there will always be enough data in the rx fifo - * to satisfy a burst, and there will always be enough space in the - * tx fifo to accept a burst (a tx burst will overwrite the fifo if - * there is not enough space), there must always remain enough empty - * space in the rx fifo for any data loaded to the tx fifo. - * Whenever burst_size (in bytes) equals bits/word, the fifo threshold - * will be 8, or half the fifo; - * The threshold can only be set to 2, 4 or 8, but not 16, because - * to burst 16 to the tx fifo, the fifo would have to be empty; - * however, the minimum fifo trigger level is 1, and the tx will - * request service when the fifo is at this level, with only 15 spaces. - */ - - /* find bytes/word */ - if (bits_per_word <= 8) - bytes_per_word = 1; - else if (bits_per_word <= 16) - bytes_per_word = 2; - else - bytes_per_word = 4; - - /* use struct pxa2xx_spi_chip->dma_burst_size if available */ - if (chip_info) - req_burst_size = chip_info->dma_burst_size; - else { - switch (chip->dma_burst_size) { - default: - /* if the default burst size is not set, - * do it now */ - chip->dma_burst_size = DCMD_BURST8; - case DCMD_BURST8: - req_burst_size = 8; - break; - case DCMD_BURST16: - req_burst_size = 16; - break; - case DCMD_BURST32: - req_burst_size = 32; - break; - } - } - if (req_burst_size <= 8) { - *burst_code = DCMD_BURST8; - burst_bytes = 8; - } else if (req_burst_size <= 16) { - if (bytes_per_word == 1) { - /* don't burst more than 1/2 the fifo */ - *burst_code = DCMD_BURST8; - burst_bytes = 8; - retval = 1; - } else { - *burst_code = DCMD_BURST16; - burst_bytes = 16; - } - } else { - if (bytes_per_word == 1) { - /* don't burst more than 1/2 the fifo */ - *burst_code = DCMD_BURST8; - burst_bytes = 8; - retval = 1; - } else if (bytes_per_word == 2) { - /* don't burst more than 1/2 the fifo */ - *burst_code = DCMD_BURST16; - burst_bytes = 16; - retval = 1; - } else { - *burst_code = DCMD_BURST32; - burst_bytes = 32; - } - } - - thresh_words = burst_bytes / bytes_per_word; - - /* thresh_words will be between 2 and 8 */ - *threshold = (SSCR1_RxTresh(thresh_words) & SSCR1_RFT) - | (SSCR1_TxTresh(16-thresh_words) & SSCR1_TFT); - - return retval; -} - static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate) { unsigned long ssp_clk = drv_data->max_clk_rate; @@ -956,8 +622,8 @@ static void pump_transfers(unsigned long data) cs_deassert(drv_data); } - /* Check for transfers that need multiple DMA segments */ - if (transfer->len > MAX_DMA_LEN && chip->enable_dma) { + /* Check if we can DMA this transfer */ + if (!pxa2xx_spi_dma_is_possible(transfer->len) && chip->enable_dma) { /* reject already-mapped transfers; PIO won't always work */ if (message->is_dma_mapped @@ -980,21 +646,20 @@ static void pump_transfers(unsigned long data) } /* Setup the transfer state based on the type of transfer */ - if (flush(drv_data) == 0) { + if (pxa2xx_spi_flush(drv_data) == 0) { dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n"); message->status = -EIO; giveback(drv_data); return; } drv_data->n_bytes = chip->n_bytes; - drv_data->dma_width = chip->dma_width; drv_data->tx = (void *)transfer->tx_buf; drv_data->tx_end = drv_data->tx + transfer->len; drv_data->rx = transfer->rx_buf; drv_data->rx_end = drv_data->rx + transfer->len; drv_data->rx_dma = transfer->rx_dma; drv_data->tx_dma = transfer->tx_dma; - drv_data->len = transfer->len & DCMD_LENGTH; + drv_data->len = transfer->len; drv_data->write = drv_data->tx ? chip->write : null_writer; drv_data->read = drv_data->rx ? chip->read : null_reader; @@ -1015,21 +680,18 @@ static void pump_transfers(unsigned long data) if (bits <= 8) { drv_data->n_bytes = 1; - drv_data->dma_width = DCMD_WIDTH1; drv_data->read = drv_data->read != null_reader ? u8_reader : null_reader; drv_data->write = drv_data->write != null_writer ? u8_writer : null_writer; } else if (bits <= 16) { drv_data->n_bytes = 2; - drv_data->dma_width = DCMD_WIDTH2; drv_data->read = drv_data->read != null_reader ? u16_reader : null_reader; drv_data->write = drv_data->write != null_writer ? u16_writer : null_writer; } else if (bits <= 32) { drv_data->n_bytes = 4; - drv_data->dma_width = DCMD_WIDTH4; drv_data->read = drv_data->read != null_reader ? u32_reader : null_reader; drv_data->write = drv_data->write != null_writer ? @@ -1038,7 +700,8 @@ static void pump_transfers(unsigned long data) /* if bits/word is changed in dma mode, then must check the * thresholds and burst also */ if (chip->enable_dma) { - if (set_dma_burst_and_threshold(chip, message->spi, + if (pxa2xx_spi_set_dma_burst_and_threshold(chip, + message->spi, bits, &dma_burst, &dma_thresh)) if (printk_ratelimit()) @@ -1057,70 +720,21 @@ static void pump_transfers(unsigned long data) message->state = RUNNING_STATE; - /* Try to map dma buffer and do a dma transfer if successful, but - * only if the length is non-zero and less than MAX_DMA_LEN. - * - * Zero-length non-descriptor DMA is illegal on PXA2xx; force use - * of PIO instead. Care is needed above because the transfer may - * have have been passed with buffers that are already dma mapped. - * A zero-length transfer in PIO mode will not try to write/read - * to/from the buffers - * - * REVISIT large transfers are exactly where we most want to be - * using DMA. If this happens much, split those transfers into - * multiple DMA segments rather than forcing PIO. - */ drv_data->dma_mapped = 0; - if (drv_data->len > 0 && drv_data->len <= MAX_DMA_LEN) - drv_data->dma_mapped = map_dma_buffers(drv_data); + if (pxa2xx_spi_dma_is_possible(drv_data->len)) + drv_data->dma_mapped = pxa2xx_spi_map_dma_buffers(drv_data); if (drv_data->dma_mapped) { /* Ensure we have the correct interrupt handler */ - drv_data->transfer_handler = dma_transfer; - - /* Setup rx DMA Channel */ - DCSR(drv_data->rx_channel) = RESET_DMA_CHANNEL; - DSADR(drv_data->rx_channel) = drv_data->ssdr_physical; - DTADR(drv_data->rx_channel) = drv_data->rx_dma; - if (drv_data->rx == drv_data->null_dma_buf) - /* No target address increment */ - DCMD(drv_data->rx_channel) = DCMD_FLOWSRC - | drv_data->dma_width - | dma_burst - | drv_data->len; - else - DCMD(drv_data->rx_channel) = DCMD_INCTRGADDR - | DCMD_FLOWSRC - | drv_data->dma_width - | dma_burst - | drv_data->len; - - /* Setup tx DMA Channel */ - DCSR(drv_data->tx_channel) = RESET_DMA_CHANNEL; - DSADR(drv_data->tx_channel) = drv_data->tx_dma; - DTADR(drv_data->tx_channel) = drv_data->ssdr_physical; - if (drv_data->tx == drv_data->null_dma_buf) - /* No source address increment */ - DCMD(drv_data->tx_channel) = DCMD_FLOWTRG - | drv_data->dma_width - | dma_burst - | drv_data->len; - else - DCMD(drv_data->tx_channel) = DCMD_INCSRCADDR - | DCMD_FLOWTRG - | drv_data->dma_width - | dma_burst - | drv_data->len; - - /* Enable dma end irqs on SSP to detect end of transfer */ - if (drv_data->ssp_type == PXA25x_SSP) - DCMD(drv_data->tx_channel) |= DCMD_ENDIRQEN; + drv_data->transfer_handler = pxa2xx_spi_dma_transfer; + + pxa2xx_spi_dma_prepare(drv_data, dma_burst); /* Clear status and start DMA engine */ cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1; write_SSSR(drv_data->clear_sr, reg); - DCSR(drv_data->rx_channel) |= DCSR_RUN; - DCSR(drv_data->tx_channel) |= DCSR_RUN; + + pxa2xx_spi_dma_start(drv_data); } else { /* Ensure we have the correct interrupt handler */ drv_data->transfer_handler = interrupt_transfer; @@ -1130,6 +744,13 @@ static void pump_transfers(unsigned long data) write_SSSR_CS(drv_data, drv_data->clear_sr); } + if (is_lpss_ssp(drv_data)) { + if ((read_SSIRF(reg) & 0xff) != chip->lpss_rx_threshold) + write_SSIRF(chip->lpss_rx_threshold, reg); + if ((read_SSITF(reg) & 0xffff) != chip->lpss_tx_threshold) + write_SSITF(chip->lpss_tx_threshold, reg); + } + /* see if we need to reload the config registers */ if ((read_SSCR0(reg) != cr0) || (read_SSCR1(reg) & SSCR1_CHANGE_MASK) != @@ -1177,6 +798,27 @@ static int pxa2xx_spi_transfer_one_message(struct spi_master *master, return 0; } +static int pxa2xx_spi_prepare_transfer(struct spi_master *master) +{ + struct driver_data *drv_data = spi_master_get_devdata(master); + + pm_runtime_get_sync(&drv_data->pdev->dev); + return 0; +} + +static int pxa2xx_spi_unprepare_transfer(struct spi_master *master) +{ + struct driver_data *drv_data = spi_master_get_devdata(master); + + /* Disable the SSP now */ + write_SSCR0(read_SSCR0(drv_data->ioaddr) & ~SSCR0_SSE, + drv_data->ioaddr); + + pm_runtime_mark_last_busy(&drv_data->pdev->dev); + pm_runtime_put_autosuspend(&drv_data->pdev->dev); + return 0; +} + static int setup_cs(struct spi_device *spi, struct chip_data *chip, struct pxa2xx_spi_chip *chip_info) { @@ -1221,8 +863,17 @@ static int setup(struct spi_device *spi) struct chip_data *chip; struct driver_data *drv_data = spi_master_get_devdata(spi->master); unsigned int clk_div; - uint tx_thres = TX_THRESH_DFLT; - uint rx_thres = RX_THRESH_DFLT; + uint tx_thres, tx_hi_thres, rx_thres; + + if (is_lpss_ssp(drv_data)) { + tx_thres = LPSS_TX_LOTHRESH_DFLT; + tx_hi_thres = LPSS_TX_HITHRESH_DFLT; + rx_thres = LPSS_RX_THRESH_DFLT; + } else { + tx_thres = TX_THRESH_DFLT; + tx_hi_thres = 0; + rx_thres = RX_THRESH_DFLT; + } if (!pxa25x_ssp_comp(drv_data) && (spi->bits_per_word < 4 || spi->bits_per_word > 32)) { @@ -1262,8 +913,6 @@ static int setup(struct spi_device *spi) chip->gpio_cs = -1; chip->enable_dma = 0; chip->timeout = TIMOUT_DFLT; - chip->dma_burst_size = drv_data->master_info->enable_dma ? - DCMD_BURST8 : 0; } /* protocol drivers may change the chip settings, so... @@ -1277,23 +926,37 @@ static int setup(struct spi_device *spi) chip->timeout = chip_info->timeout; if (chip_info->tx_threshold) tx_thres = chip_info->tx_threshold; + if (chip_info->tx_hi_threshold) + tx_hi_thres = chip_info->tx_hi_threshold; if (chip_info->rx_threshold) rx_thres = chip_info->rx_threshold; chip->enable_dma = drv_data->master_info->enable_dma; chip->dma_threshold = 0; if (chip_info->enable_loopback) chip->cr1 = SSCR1_LBM; + } else if (ACPI_HANDLE(&spi->dev)) { + /* + * Slave devices enumerated from ACPI namespace don't + * usually have chip_info but we still might want to use + * DMA with them. + */ + chip->enable_dma = drv_data->master_info->enable_dma; } chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) | (SSCR1_TxTresh(tx_thres) & SSCR1_TFT); + chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres); + chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres) + | SSITF_TxHiThresh(tx_hi_thres); + /* set dma burst and threshold outside of chip_info path so that if * chip_info goes away after setting chip->enable_dma, the * burst and threshold can still respond to changes in bits_per_word */ if (chip->enable_dma) { /* set up legal burst and threshold for dma */ - if (set_dma_burst_and_threshold(chip, spi, spi->bits_per_word, + if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi, + spi->bits_per_word, &chip->dma_burst_size, &chip->dma_threshold)) { dev_warn(&spi->dev, "in setup: DMA burst size reduced " @@ -1314,6 +977,9 @@ static int setup(struct spi_device *spi) chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0) | (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0); + if (spi->mode & SPI_LOOP) + chip->cr1 |= SSCR1_LBM; + /* NOTE: PXA25x_SSP _could_ use external clocking ... */ if (!pxa25x_ssp_comp(drv_data)) dev_dbg(&spi->dev, "%ld Hz actual, %s\n", @@ -1328,18 +994,15 @@ static int setup(struct spi_device *spi) if (spi->bits_per_word <= 8) { chip->n_bytes = 1; - chip->dma_width = DCMD_WIDTH1; chip->read = u8_reader; chip->write = u8_writer; } else if (spi->bits_per_word <= 16) { chip->n_bytes = 2; - chip->dma_width = DCMD_WIDTH2; chip->read = u16_reader; chip->write = u16_writer; } else if (spi->bits_per_word <= 32) { chip->cr0 |= SSCR0_EDSS; chip->n_bytes = 4; - chip->dma_width = DCMD_WIDTH4; chip->read = u32_reader; chip->write = u32_writer; } else { @@ -1370,6 +1033,99 @@ static void cleanup(struct spi_device *spi) kfree(chip); } +#ifdef CONFIG_ACPI +static int pxa2xx_spi_acpi_add_dma(struct acpi_resource *res, void *data) +{ + struct pxa2xx_spi_master *pdata = data; + + if (res->type == ACPI_RESOURCE_TYPE_FIXED_DMA) { + const struct acpi_resource_fixed_dma *dma; + + dma = &res->data.fixed_dma; + if (pdata->tx_slave_id < 0) { + pdata->tx_slave_id = dma->request_lines; + pdata->tx_chan_id = dma->channels; + } else if (pdata->rx_slave_id < 0) { + pdata->rx_slave_id = dma->request_lines; + pdata->rx_chan_id = dma->channels; + } + } + + /* Tell the ACPI core to skip this resource */ + return 1; +} + +static struct pxa2xx_spi_master * +pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev) +{ + struct pxa2xx_spi_master *pdata; + struct list_head resource_list; + struct acpi_device *adev; + struct ssp_device *ssp; + struct resource *res; + int devid; + + if (!ACPI_HANDLE(&pdev->dev) || + acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev)) + return NULL; + + pdata = devm_kzalloc(&pdev->dev, sizeof(*ssp), GFP_KERNEL); + if (!pdata) { + dev_err(&pdev->dev, + "failed to allocate memory for platform data\n"); + return NULL; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return NULL; + + ssp = &pdata->ssp; + + ssp->phys_base = res->start; + ssp->mmio_base = devm_request_and_ioremap(&pdev->dev, res); + if (!ssp->mmio_base) { + dev_err(&pdev->dev, "failed to ioremap mmio_base\n"); + return NULL; + } + + ssp->clk = devm_clk_get(&pdev->dev, NULL); + ssp->irq = platform_get_irq(pdev, 0); + ssp->type = LPSS_SSP; + ssp->pdev = pdev; + + ssp->port_id = -1; + if (adev->pnp.unique_id && !kstrtoint(adev->pnp.unique_id, 0, &devid)) + ssp->port_id = devid; + + pdata->num_chipselect = 1; + pdata->rx_slave_id = -1; + pdata->tx_slave_id = -1; + + INIT_LIST_HEAD(&resource_list); + acpi_dev_get_resources(adev, &resource_list, pxa2xx_spi_acpi_add_dma, + pdata); + acpi_dev_free_resource_list(&resource_list); + + pdata->enable_dma = pdata->rx_slave_id >= 0 && pdata->tx_slave_id >= 0; + + return pdata; +} + +static struct acpi_device_id pxa2xx_spi_acpi_match[] = { + { "INT33C0", 0 }, + { "INT33C1", 0 }, + { }, +}; +MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match); +#else +static inline struct pxa2xx_spi_master * +pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev) +{ + return NULL; +} +#endif + static int pxa2xx_spi_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -1381,8 +1137,11 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) platform_info = dev_get_platdata(dev); if (!platform_info) { - dev_err(&pdev->dev, "missing platform data\n"); - return -ENODEV; + platform_info = pxa2xx_spi_acpi_get_pdata(pdev); + if (!platform_info) { + dev_err(&pdev->dev, "missing platform data\n"); + return -ENODEV; + } } ssp = pxa_ssp_request(pdev->id, pdev->name); @@ -1409,8 +1168,9 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) master->dev.parent = &pdev->dev; master->dev.of_node = pdev->dev.of_node; + ACPI_HANDLE_SET(&master->dev, ACPI_HANDLE(&pdev->dev)); /* the spi->mode bits understood by this driver: */ - master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP; master->bus_num = ssp->port_id; master->num_chipselect = platform_info->num_chipselect; @@ -1418,6 +1178,8 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) master->cleanup = cleanup; master->setup = setup; master->transfer_one_message = pxa2xx_spi_transfer_one_message; + master->prepare_transfer_hardware = pxa2xx_spi_prepare_transfer; + master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer; drv_data->ssp_type = ssp->type; drv_data->null_dma_buf = (u32 *)PTR_ALIGN(&drv_data[1], DMA_ALIGNMENT); @@ -1431,7 +1193,7 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR; } else { drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE; - drv_data->dma_cr1 = SSCR1_TSRE | SSCR1_RSRE | SSCR1_TINTE; + drv_data->dma_cr1 = DEFAULT_DMA_CR1; drv_data->clear_sr = SSSR_ROR | SSSR_TINT; drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR; } @@ -1447,31 +1209,11 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) drv_data->tx_channel = -1; drv_data->rx_channel = -1; if (platform_info->enable_dma) { - - /* Get two DMA channels (rx and tx) */ - drv_data->rx_channel = pxa_request_dma("pxa2xx_spi_ssp_rx", - DMA_PRIO_HIGH, - dma_handler, - drv_data); - if (drv_data->rx_channel < 0) { - dev_err(dev, "problem (%d) requesting rx channel\n", - drv_data->rx_channel); - status = -ENODEV; - goto out_error_irq_alloc; - } - drv_data->tx_channel = pxa_request_dma("pxa2xx_spi_ssp_tx", - DMA_PRIO_MEDIUM, - dma_handler, - drv_data); - if (drv_data->tx_channel < 0) { - dev_err(dev, "problem (%d) requesting tx channel\n", - drv_data->tx_channel); - status = -ENODEV; - goto out_error_dma_alloc; + status = pxa2xx_spi_dma_setup(drv_data); + if (status) { + dev_warn(dev, "failed to setup DMA, using PIO\n"); + platform_info->enable_dma = false; } - - DRCMR(ssp->drcmr_rx) = DRCMR_MAPVLD | drv_data->rx_channel; - DRCMR(ssp->drcmr_tx) = DRCMR_MAPVLD | drv_data->tx_channel; } /* Enable SOC clock */ @@ -1492,6 +1234,8 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) write_SSTO(0, drv_data->ioaddr); write_SSPSP(0, drv_data->ioaddr); + lpss_ssp_setup(drv_data); + tasklet_init(&drv_data->pump_transfers, pump_transfers, (unsigned long)drv_data); @@ -1503,18 +1247,16 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) goto out_error_clock_enabled; } + pm_runtime_set_autosuspend_delay(&pdev->dev, 50); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + return status; out_error_clock_enabled: clk_disable_unprepare(ssp->clk); - -out_error_dma_alloc: - if (drv_data->tx_channel != -1) - pxa_free_dma(drv_data->tx_channel); - if (drv_data->rx_channel != -1) - pxa_free_dma(drv_data->rx_channel); - -out_error_irq_alloc: + pxa2xx_spi_dma_release(drv_data); free_irq(ssp->irq, drv_data); out_error_master_alloc: @@ -1532,17 +1274,18 @@ static int pxa2xx_spi_remove(struct platform_device *pdev) return 0; ssp = drv_data->ssp; + pm_runtime_get_sync(&pdev->dev); + /* Disable the SSP at the peripheral and SOC level */ write_SSCR0(0, drv_data->ioaddr); clk_disable_unprepare(ssp->clk); /* Release DMA */ - if (drv_data->master_info->enable_dma) { - DRCMR(ssp->drcmr_rx) = 0; - DRCMR(ssp->drcmr_tx) = 0; - pxa_free_dma(drv_data->tx_channel); - pxa_free_dma(drv_data->rx_channel); - } + if (drv_data->master_info->enable_dma) + pxa2xx_spi_dma_release(drv_data); + + pm_runtime_put_noidle(&pdev->dev); + pm_runtime_disable(&pdev->dev); /* Release IRQ */ free_irq(ssp->irq, drv_data); @@ -1589,12 +1332,7 @@ static int pxa2xx_spi_resume(struct device *dev) struct ssp_device *ssp = drv_data->ssp; int status = 0; - if (drv_data->rx_channel != -1) - DRCMR(drv_data->ssp->drcmr_rx) = - DRCMR_MAPVLD | drv_data->rx_channel; - if (drv_data->tx_channel != -1) - DRCMR(drv_data->ssp->drcmr_tx) = - DRCMR_MAPVLD | drv_data->tx_channel; + pxa2xx_spi_dma_resume(drv_data); /* Enable the SSP clock */ clk_prepare_enable(ssp->clk); @@ -1608,20 +1346,38 @@ static int pxa2xx_spi_resume(struct device *dev) return 0; } +#endif + +#ifdef CONFIG_PM_RUNTIME +static int pxa2xx_spi_runtime_suspend(struct device *dev) +{ + struct driver_data *drv_data = dev_get_drvdata(dev); + + clk_disable_unprepare(drv_data->ssp->clk); + return 0; +} + +static int pxa2xx_spi_runtime_resume(struct device *dev) +{ + struct driver_data *drv_data = dev_get_drvdata(dev); + + clk_prepare_enable(drv_data->ssp->clk); + return 0; +} +#endif static const struct dev_pm_ops pxa2xx_spi_pm_ops = { - .suspend = pxa2xx_spi_suspend, - .resume = pxa2xx_spi_resume, + SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume) + SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend, + pxa2xx_spi_runtime_resume, NULL) }; -#endif static struct platform_driver driver = { .driver = { .name = "pxa2xx-spi", .owner = THIS_MODULE, -#ifdef CONFIG_PM .pm = &pxa2xx_spi_pm_ops, -#endif + .acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match), }, .probe = pxa2xx_spi_probe, .remove = pxa2xx_spi_remove, diff --git a/drivers/spi/spi-pxa2xx.h b/drivers/spi/spi-pxa2xx.h new file mode 100644 index 000000000000..5adc2a11c7bc --- /dev/null +++ b/drivers/spi/spi-pxa2xx.h @@ -0,0 +1,221 @@ +/* + * Copyright (C) 2005 Stephen Street / StreetFire Sound Labs + * Copyright (C) 2013, Intel Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef SPI_PXA2XX_H +#define SPI_PXA2XX_H + +#include <linux/atomic.h> +#include <linux/dmaengine.h> +#include <linux/errno.h> +#include <linux/io.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/pxa2xx_ssp.h> +#include <linux/scatterlist.h> +#include <linux/sizes.h> +#include <linux/spi/spi.h> +#include <linux/spi/pxa2xx_spi.h> + +struct driver_data { + /* Driver model hookup */ + struct platform_device *pdev; + + /* SSP Info */ + struct ssp_device *ssp; + + /* SPI framework hookup */ + enum pxa_ssp_type ssp_type; + struct spi_master *master; + + /* PXA hookup */ + struct pxa2xx_spi_master *master_info; + + /* PXA private DMA setup stuff */ + int rx_channel; + int tx_channel; + u32 *null_dma_buf; + + /* SSP register addresses */ + void __iomem *ioaddr; + u32 ssdr_physical; + + /* SSP masks*/ + u32 dma_cr1; + u32 int_cr1; + u32 clear_sr; + u32 mask_sr; + + /* Maximun clock rate */ + unsigned long max_clk_rate; + + /* Message Transfer pump */ + struct tasklet_struct pump_transfers; + + /* DMA engine support */ + struct dma_chan *rx_chan; + struct dma_chan *tx_chan; + struct sg_table rx_sgt; + struct sg_table tx_sgt; + int rx_nents; + int tx_nents; + void *dummy; + atomic_t dma_running; + + /* Current message transfer state info */ + struct spi_message *cur_msg; + struct spi_transfer *cur_transfer; + struct chip_data *cur_chip; + size_t len; + void *tx; + void *tx_end; + void *rx; + void *rx_end; + int dma_mapped; + dma_addr_t rx_dma; + dma_addr_t tx_dma; + size_t rx_map_len; + size_t tx_map_len; + u8 n_bytes; + int (*write)(struct driver_data *drv_data); + int (*read)(struct driver_data *drv_data); + irqreturn_t (*transfer_handler)(struct driver_data *drv_data); + void (*cs_control)(u32 command); + + void __iomem *lpss_base; +}; + +struct chip_data { + u32 cr0; + u32 cr1; + u32 psp; + u32 timeout; + u8 n_bytes; + u32 dma_burst_size; + u32 threshold; + u32 dma_threshold; + u16 lpss_rx_threshold; + u16 lpss_tx_threshold; + u8 enable_dma; + u8 bits_per_word; + u32 speed_hz; + union { + int gpio_cs; + unsigned int frm; + }; + int gpio_cs_inverted; + int (*write)(struct driver_data *drv_data); + int (*read)(struct driver_data *drv_data); + void (*cs_control)(u32 command); +}; + +#define DEFINE_SSP_REG(reg, off) \ +static inline u32 read_##reg(void const __iomem *p) \ +{ return __raw_readl(p + (off)); } \ +\ +static inline void write_##reg(u32 v, void __iomem *p) \ +{ __raw_writel(v, p + (off)); } + +DEFINE_SSP_REG(SSCR0, 0x00) +DEFINE_SSP_REG(SSCR1, 0x04) +DEFINE_SSP_REG(SSSR, 0x08) +DEFINE_SSP_REG(SSITR, 0x0c) +DEFINE_SSP_REG(SSDR, 0x10) +DEFINE_SSP_REG(SSTO, 0x28) +DEFINE_SSP_REG(SSPSP, 0x2c) +DEFINE_SSP_REG(SSITF, SSITF) +DEFINE_SSP_REG(SSIRF, SSIRF) + +#define START_STATE ((void *)0) +#define RUNNING_STATE ((void *)1) +#define DONE_STATE ((void *)2) +#define ERROR_STATE ((void *)-1) + +#define IS_DMA_ALIGNED(x) IS_ALIGNED((unsigned long)(x), DMA_ALIGNMENT) +#define DMA_ALIGNMENT 8 + +static inline int pxa25x_ssp_comp(struct driver_data *drv_data) +{ + if (drv_data->ssp_type == PXA25x_SSP) + return 1; + if (drv_data->ssp_type == CE4100_SSP) + return 1; + return 0; +} + +static inline void write_SSSR_CS(struct driver_data *drv_data, u32 val) +{ + void __iomem *reg = drv_data->ioaddr; + + if (drv_data->ssp_type == CE4100_SSP) + val |= read_SSSR(reg) & SSSR_ALT_FRM_MASK; + + write_SSSR(val, reg); +} + +extern int pxa2xx_spi_flush(struct driver_data *drv_data); +extern void *pxa2xx_spi_next_transfer(struct driver_data *drv_data); + +/* + * Select the right DMA implementation. + */ +#if defined(CONFIG_SPI_PXA2XX_PXADMA) +#define SPI_PXA2XX_USE_DMA 1 +#define MAX_DMA_LEN 8191 +#define DEFAULT_DMA_CR1 (SSCR1_TSRE | SSCR1_RSRE | SSCR1_TINTE) +#elif defined(CONFIG_SPI_PXA2XX_DMA) +#define SPI_PXA2XX_USE_DMA 1 +#define MAX_DMA_LEN SZ_64K +#define DEFAULT_DMA_CR1 (SSCR1_TSRE | SSCR1_RSRE | SSCR1_TRAIL) +#else +#undef SPI_PXA2XX_USE_DMA +#define MAX_DMA_LEN 0 +#define DEFAULT_DMA_CR1 0 +#endif + +#ifdef SPI_PXA2XX_USE_DMA +extern bool pxa2xx_spi_dma_is_possible(size_t len); +extern int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data); +extern irqreturn_t pxa2xx_spi_dma_transfer(struct driver_data *drv_data); +extern int pxa2xx_spi_dma_prepare(struct driver_data *drv_data, u32 dma_burst); +extern void pxa2xx_spi_dma_start(struct driver_data *drv_data); +extern int pxa2xx_spi_dma_setup(struct driver_data *drv_data); +extern void pxa2xx_spi_dma_release(struct driver_data *drv_data); +extern void pxa2xx_spi_dma_resume(struct driver_data *drv_data); +extern int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip, + struct spi_device *spi, + u8 bits_per_word, + u32 *burst_code, + u32 *threshold); +#else +static inline bool pxa2xx_spi_dma_is_possible(size_t len) { return false; } +static inline int pxa2xx_spi_map_dma_buffers(struct driver_data *drv_data) +{ + return 0; +} +#define pxa2xx_spi_dma_transfer NULL +static inline void pxa2xx_spi_dma_prepare(struct driver_data *drv_data, + u32 dma_burst) {} +static inline void pxa2xx_spi_dma_start(struct driver_data *drv_data) {} +static inline int pxa2xx_spi_dma_setup(struct driver_data *drv_data) +{ + return 0; +} +static inline void pxa2xx_spi_dma_release(struct driver_data *drv_data) {} +static inline void pxa2xx_spi_dma_resume(struct driver_data *drv_data) {} +static inline int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip, + struct spi_device *spi, + u8 bits_per_word, + u32 *burst_code, + u32 *threshold) +{ + return -ENODEV; +} +#endif + +#endif /* SPI_PXA2XX_H */ |