diff options
author | Hein_Tibosch <hein_tibosch@yahoo.es> | 2012-08-30 16:34:38 +0000 |
---|---|---|
committer | Chris Ball <cjb@laptop.org> | 2012-10-03 10:05:22 -0400 |
commit | ccdfe6122f61b40592820d48b4cde021295418a0 (patch) | |
tree | 79863d1a3442cee855f3e693d7d6cc7923b462a2 /drivers/mmc/host/atmel-mci.c | |
parent | ac940938df138acd241dc5ae9a933416da036a35 (diff) | |
download | linux-ccdfe6122f61b40592820d48b4cde021295418a0.tar.bz2 |
mmc: atmel-mci: DMA can be used with other controllers
After the latest changes to atmel-mci, it could not be used with
DMA on the AVR32 platform. This patch will allow to use DMA again
and it will avoid access to MCI register ATMCI_DMA.
Even if the IP version is lower than v3xx and doesn't have the DMA
configuration register, DMA transfers can be used with a different
controller than the Atmel AHB DMA one. For instance, some AVR chips
use the Synopsys DesignWare AHB DMA controller.
Signed-off-by: Hein Tibosch <hein_tibosch@yahoo.es>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Diffstat (limited to 'drivers/mmc/host/atmel-mci.c')
-rw-r--r-- | drivers/mmc/host/atmel-mci.c | 26 |
1 files changed, 13 insertions, 13 deletions
diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c index 8c72828239b2..6823d963376e 100644 --- a/drivers/mmc/host/atmel-mci.c +++ b/drivers/mmc/host/atmel-mci.c @@ -74,7 +74,7 @@ enum atmci_pdc_buf { }; struct atmel_mci_caps { - bool has_dma; + bool has_dma_conf_reg; bool has_pdc; bool has_cfg_reg; bool has_cstor_reg; @@ -421,7 +421,7 @@ static int atmci_regs_show(struct seq_file *s, void *v) atmci_show_status_reg(s, "SR", buf[ATMCI_SR / 4]); atmci_show_status_reg(s, "IMR", buf[ATMCI_IMR / 4]); - if (host->caps.has_dma) { + if (host->caps.has_dma_conf_reg) { u32 val; val = buf[ATMCI_DMA / 4]; @@ -841,7 +841,7 @@ static void atmci_dma_complete(void *arg) dev_vdbg(&host->pdev->dev, "DMA complete\n"); - if (host->caps.has_dma) + if (host->caps.has_dma_conf_reg) /* Disable DMA hardware handshaking on MCI */ atmci_writel(host, ATMCI_DMA, atmci_readl(host, ATMCI_DMA) & ~ATMCI_DMAEN); @@ -1028,7 +1028,9 @@ atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data) maxburst = atmci_convert_chksize(host->dma_conf.dst_maxburst); } - atmci_writel(host, ATMCI_DMA, ATMCI_DMA_CHKSIZE(maxburst) | ATMCI_DMAEN); + if (host->caps.has_dma_conf_reg) + atmci_writel(host, ATMCI_DMA, ATMCI_DMA_CHKSIZE(maxburst) | + ATMCI_DMAEN); sglen = dma_map_sg(chan->device->dev, data->sg, data->sg_len, direction); @@ -2243,7 +2245,10 @@ static bool atmci_configure_dma(struct atmel_mci *host) pdata = host->pdev->dev.platform_data; - if (pdata && find_slave_dev(pdata->dma_slave)) { + if (!pdata) + return false; + + if (pdata->dma_slave && find_slave_dev(pdata->dma_slave)) { dma_cap_mask_t mask; /* Try to grab a DMA channel */ @@ -2284,7 +2289,7 @@ static void __init atmci_get_cap(struct atmel_mci *host) dev_info(&host->pdev->dev, "version: 0x%x\n", version); - host->caps.has_dma = 0; + host->caps.has_dma_conf_reg = 0; host->caps.has_pdc = 1; host->caps.has_cfg_reg = 0; host->caps.has_cstor_reg = 0; @@ -2302,12 +2307,7 @@ static void __init atmci_get_cap(struct atmel_mci *host) host->caps.has_odd_clk_div = 1; case 0x400: case 0x300: -#ifdef CONFIG_AT_HDMAC - host->caps.has_dma = 1; -#else - dev_info(&host->pdev->dev, - "has dma capability but dma engine is not selected, then use pio\n"); -#endif + host->caps.has_dma_conf_reg = 1; host->caps.has_pdc = 0; host->caps.has_cfg_reg = 1; host->caps.has_cstor_reg = 1; @@ -2388,7 +2388,7 @@ static int __init atmci_probe(struct platform_device *pdev) /* Get MCI capabilities and set operations according to it */ atmci_get_cap(host); - if (host->caps.has_dma && atmci_configure_dma(host)) { + if (atmci_configure_dma(host)) { host->prepare_data = &atmci_prepare_data_dma; host->submit_data = &atmci_submit_data_dma; host->stop_transfer = &atmci_stop_transfer_dma; |