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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-08-25 11:09:35 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-08-25 11:09:35 -0700
commit39bdc95871b57828b3bbefc0280a1a80a6b63d9e (patch)
treefb4cc664f4e07d1e49f60e743cc80096bc973182 /drivers/iio/adc/rockchip_saradc.c
parented7f92da59f24dd966555efef978fe14085b3318 (diff)
parentff9e7621586ff8b86a18cfbb7c437c277ebc1970 (diff)
downloadlinux-39bdc95871b57828b3bbefc0280a1a80a6b63d9e.tar.bz2
Merge tag 'iio-for-3.18a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into work-next
Jonathan writes: 1st round of new IIO drivers, functionality and cleanups for the 3.18 cycle. Maintainer Updates * Add 3 designated reviewers for IIO. Lars, Peter and Hartmut have been actively reviewing a lot of patches for a while now so this reflects the status quo. These three are probably the only reason I keep my head above the water! New drivers and device support * max5821 DAC * Rockchip SARADC * TI ADC128S052 ADC * BMC150 Accelerometer * exynos ADC driver gains support for s3c24xx and s3c64xx parts. * kxcjk-1013 gainst range control and runtime PM support to drive down it's power usage. Driver removals * Drop ad5930, ad99850, ad9852, ad9910 and ad9951 drivers on the simple basis that they drivers just provided a register write function with no compliant user space ABI whatsoever. Much better to drop them and start again for these in the fullness of time. Core Enhancements * Join together neighbouring elements in the demux units that feeds the binary interfaces. This cuts down on the number of individual copies needed when splitting out individual channels from the incoming channel scans. * Other demux related cleanups such as using roundup instead of a local implementation. Cleanups * Drop an unnecessary double setting of the owner field in xilinx adc. * Some more patches to use managed (devm) interfaces to cut down on complexity of removal code. * adis16060 coding style fixlets. * Fix some incorrect error returns in the Xilinx ADC driver. * Coding style fixlets for various accelerometer drivers. * Some sparse warning fixes to do with endianness and sign of variables. * Fix an incorrect and entirely pointless use of sizeof on a dynamic pointer in hid-sensor-magn-3d by dropping the relevant code.
Diffstat (limited to 'drivers/iio/adc/rockchip_saradc.c')
-rw-r--r--drivers/iio/adc/rockchip_saradc.c317
1 files changed, 317 insertions, 0 deletions
diff --git a/drivers/iio/adc/rockchip_saradc.c b/drivers/iio/adc/rockchip_saradc.c
new file mode 100644
index 000000000000..1fad9647cef4
--- /dev/null
+++ b/drivers/iio/adc/rockchip_saradc.c
@@ -0,0 +1,317 @@
+/*
+ * Rockchip Successive Approximation Register (SAR) A/D Converter
+ * Copyright (C) 2014 ROCKCHIP, Inc.
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/regulator/consumer.h>
+#include <linux/iio/iio.h>
+
+#define SARADC_DATA 0x00
+#define SARADC_DATA_MASK 0x3ff
+
+#define SARADC_STAS 0x04
+#define SARADC_STAS_BUSY BIT(0)
+
+#define SARADC_CTRL 0x08
+#define SARADC_CTRL_IRQ_STATUS BIT(6)
+#define SARADC_CTRL_IRQ_ENABLE BIT(5)
+#define SARADC_CTRL_POWER_CTRL BIT(3)
+#define SARADC_CTRL_CHN_MASK 0x7
+
+#define SARADC_DLY_PU_SOC 0x0c
+#define SARADC_DLY_PU_SOC_MASK 0x3f
+
+#define SARADC_BITS 10
+#define SARADC_TIMEOUT msecs_to_jiffies(100)
+
+struct rockchip_saradc {
+ void __iomem *regs;
+ struct clk *pclk;
+ struct clk *clk;
+ struct completion completion;
+ struct regulator *vref;
+ u16 last_val;
+};
+
+static int rockchip_saradc_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct rockchip_saradc *info = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ mutex_lock(&indio_dev->mlock);
+
+ reinit_completion(&info->completion);
+
+ /* 8 clock periods as delay between power up and start cmd */
+ writel_relaxed(8, info->regs + SARADC_DLY_PU_SOC);
+
+ /* Select the channel to be used and trigger conversion */
+ writel(SARADC_CTRL_POWER_CTRL
+ | (chan->channel & SARADC_CTRL_CHN_MASK)
+ | SARADC_CTRL_IRQ_ENABLE,
+ info->regs + SARADC_CTRL);
+
+ if (!wait_for_completion_timeout(&info->completion,
+ SARADC_TIMEOUT)) {
+ writel_relaxed(0, info->regs + SARADC_CTRL);
+ mutex_unlock(&indio_dev->mlock);
+ return -ETIMEDOUT;
+ }
+
+ *val = info->last_val;
+ mutex_unlock(&indio_dev->mlock);
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ ret = regulator_get_voltage(info->vref);
+ if (ret < 0) {
+ dev_err(&indio_dev->dev, "failed to get voltage\n");
+ return ret;
+ }
+
+ *val = ret / 1000;
+ *val2 = SARADC_BITS;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ default:
+ return -EINVAL;
+ }
+}
+
+static irqreturn_t rockchip_saradc_isr(int irq, void *dev_id)
+{
+ struct rockchip_saradc *info = (struct rockchip_saradc *)dev_id;
+
+ /* Read value */
+ info->last_val = readl_relaxed(info->regs + SARADC_DATA);
+ info->last_val &= SARADC_DATA_MASK;
+
+ /* Clear irq & power down adc */
+ writel_relaxed(0, info->regs + SARADC_CTRL);
+
+ complete(&info->completion);
+
+ return IRQ_HANDLED;
+}
+
+static const struct iio_info rockchip_saradc_iio_info = {
+ .read_raw = rockchip_saradc_read_raw,
+ .driver_module = THIS_MODULE,
+};
+
+#define ADC_CHANNEL(_index, _id) { \
+ .type = IIO_VOLTAGE, \
+ .indexed = 1, \
+ .channel = _index, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .datasheet_name = _id, \
+}
+
+static const struct iio_chan_spec rockchip_saradc_iio_channels[] = {
+ ADC_CHANNEL(0, "adc0"),
+ ADC_CHANNEL(1, "adc1"),
+ ADC_CHANNEL(2, "adc2"),
+};
+
+static int rockchip_saradc_probe(struct platform_device *pdev)
+{
+ struct rockchip_saradc *info = NULL;
+ struct device_node *np = pdev->dev.of_node;
+ struct iio_dev *indio_dev = NULL;
+ struct resource *mem;
+ int ret;
+ int irq;
+ u32 rate;
+
+ if (!np)
+ return -ENODEV;
+
+ indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
+ if (!indio_dev) {
+ dev_err(&pdev->dev, "failed allocating iio device\n");
+ return -ENOMEM;
+ }
+ info = iio_priv(indio_dev);
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ info->regs = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(info->regs))
+ return PTR_ERR(info->regs);
+
+ init_completion(&info->completion);
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "no irq resource?\n");
+ return irq;
+ }
+
+ ret = devm_request_irq(&pdev->dev, irq, rockchip_saradc_isr,
+ 0, dev_name(&pdev->dev), info);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed requesting irq %d\n", irq);
+ return ret;
+ }
+
+ info->pclk = devm_clk_get(&pdev->dev, "apb_pclk");
+ if (IS_ERR(info->pclk)) {
+ dev_err(&pdev->dev, "failed to get pclk\n");
+ return PTR_ERR(info->pclk);
+ }
+
+ info->clk = devm_clk_get(&pdev->dev, "saradc");
+ if (IS_ERR(info->clk)) {
+ dev_err(&pdev->dev, "failed to get adc clock\n");
+ return PTR_ERR(info->clk);
+ }
+
+ info->vref = devm_regulator_get(&pdev->dev, "vref");
+ if (IS_ERR(info->vref)) {
+ dev_err(&pdev->dev, "failed to get regulator, %ld\n",
+ PTR_ERR(info->vref));
+ return PTR_ERR(info->vref);
+ }
+
+ /*
+ * Use a default of 1MHz for the converter clock.
+ * This may become user-configurable in the future.
+ */
+ ret = clk_set_rate(info->clk, 1000000);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to set adc clk rate, %d\n", ret);
+ return ret;
+ }
+
+ ret = regulator_enable(info->vref);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to enable vref regulator\n");
+ return ret;
+ }
+
+ ret = clk_prepare_enable(info->pclk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to enable pclk\n");
+ goto err_reg_voltage;
+ }
+
+ ret = clk_prepare_enable(info->clk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to enable converter clock\n");
+ goto err_pclk;
+ }
+
+ platform_set_drvdata(pdev, indio_dev);
+
+ indio_dev->name = dev_name(&pdev->dev);
+ indio_dev->dev.parent = &pdev->dev;
+ indio_dev->dev.of_node = pdev->dev.of_node;
+ indio_dev->info = &rockchip_saradc_iio_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ indio_dev->channels = rockchip_saradc_iio_channels;
+ indio_dev->num_channels = ARRAY_SIZE(rockchip_saradc_iio_channels);
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ goto err_clk;
+
+ return 0;
+
+err_clk:
+ clk_disable_unprepare(info->clk);
+err_pclk:
+ clk_disable_unprepare(info->pclk);
+err_reg_voltage:
+ regulator_disable(info->vref);
+ return ret;
+}
+
+static int rockchip_saradc_remove(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct rockchip_saradc *info = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+ clk_disable_unprepare(info->clk);
+ clk_disable_unprepare(info->pclk);
+ regulator_disable(info->vref);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int rockchip_saradc_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct rockchip_saradc *info = iio_priv(indio_dev);
+
+ clk_disable_unprepare(info->clk);
+ clk_disable_unprepare(info->pclk);
+ regulator_disable(info->vref);
+
+ return 0;
+}
+
+static int rockchip_saradc_resume(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct rockchip_saradc *info = iio_priv(indio_dev);
+ int ret;
+
+ ret = regulator_enable(info->vref);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(info->pclk);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(info->clk);
+ if (ret)
+ return ret;
+
+ return ret;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(rockchip_saradc_pm_ops,
+ rockchip_saradc_suspend, rockchip_saradc_resume);
+
+static const struct of_device_id rockchip_saradc_match[] = {
+ { .compatible = "rockchip,saradc" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, rockchip_saradc_match);
+
+static struct platform_driver rockchip_saradc_driver = {
+ .probe = rockchip_saradc_probe,
+ .remove = rockchip_saradc_remove,
+ .driver = {
+ .name = "rockchip-saradc",
+ .owner = THIS_MODULE,
+ .of_match_table = rockchip_saradc_match,
+ .pm = &rockchip_saradc_pm_ops,
+ },
+};
+
+module_platform_driver(rockchip_saradc_driver);