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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-03-02 01:31:55 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-03-02 01:31:55 +0100
commitec3c13e4ac3ebeed01acc24ffba7cb1704804e07 (patch)
tree9d70554f317bc4dc7687d5c1c6eb5c36a95bea03 /drivers/iio/dac/vf610_dac.c
parentMerge 4.5-rc6 into staging-next (diff)
parentiio: adc: palmas: Drop IRQF_EARLY_RESUME flag (diff)
downloadlinux-ec3c13e4ac3ebeed01acc24ffba7cb1704804e07.tar.xz
linux-ec3c13e4ac3ebeed01acc24ffba7cb1704804e07.zip
Merge tag 'iio-for-4.6c' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next
Jonathan writes: Third set of IIO new device support, features and cleanups for the 4.6 cycle. Good to see several new contributors in this set - and more generally a number of new 'faces' over this whole cycle. Staging movements * hmc5843 - out of staging. * periodic RTC trigger - driver dropped. This is an ancient driver (brings back some memories ;) that was always somewhat of a bodge. Originally there was a driver that never went into mainline that supported large numbers of periodict timers on the PXA270 via this route. Discussions to have a generic periodic timer subsystem never went anywhere. At the time RTC periodic interrupts were real - now they are emulated using high resolution timers so with the HRT driver this has become pointless. New device support * mpu6050 driver - Add support for the mpu6500. * TI tpl0102 potentiometer - new driver. * Vybrid SoC DAC - new driver. The ADC on this SoC has been supported for a while, this adds a separate driver for the DAC. New Features * hmc5844 - Attributes to configure the bias current (typically part of a self test) This could be done before via a somewhat obscure custom interface. This at least makes it easy to tell what is going on. - Document all custom attributes. * mpu6050 - Add support for calibration offset control and readback. * ms5611 - power regulator support. This is always one that gets added the first time someone has a board that needs it. Here it was needed, hence it was added. Cleanups / minor fixes * tree wide - clean up all the myriad different return values in response to a failure of i2c_check_functionality. After discussions everyone seemed happy wiht -EOPNOTSUPP which seems to describe the situation well. I encouraged a tree wide cleanup to set a good example in future for this. * core - Typos in the iio_event_spec documentation in iio.h * afe4403 - select REGMAP_SPI to avoid dependency issues - mark suspend/resume as __maybe_unused to avoid warnings * afe4404 - mark suspend/resume as __maybe_unused to avoid warnings * atlas-ph-sensor - switch the regmap cache type from linear to rbtree to gain reading of registers on initial startup. It's not immediately obvious, but regmap flat is meant for high performances cases so doesn't read these registers. - use regmap_bulk_read in one case where it was using i2c_smbus_read_i2c_block_data directly (unlike everything else that was through regmap). * ina2xx - stype cleanups (lots of them!) * isl29018 - Get the struct device back from regmap rather than storing another copy of it in the private data. This cleanup makes sense in a number of other drivers so patches may well follow. * mpu6050 - style cleanups (lots of them!) - improved return value handling - use usleep_range to avoid the usual issues with very short msleeps. - add some missing documentation. * ms5611 - use the probed device name for the device rather than the driver name. - select IIO_BUFFER to avoid dependency issues * palmas - drop IRQF_EARLY_RESUME as no longer needed after genirq changes.
Diffstat (limited to 'drivers/iio/dac/vf610_dac.c')
-rw-r--r--drivers/iio/dac/vf610_dac.c298
1 files changed, 298 insertions, 0 deletions
diff --git a/drivers/iio/dac/vf610_dac.c b/drivers/iio/dac/vf610_dac.c
new file mode 100644
index 000000000000..c4ec7779b394
--- /dev/null
+++ b/drivers/iio/dac/vf610_dac.c
@@ -0,0 +1,298 @@
+/*
+ * Freescale Vybrid vf610 DAC driver
+ *
+ * Copyright 2016 Toradex AG
+ *
+ * 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/clk.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define VF610_DACx_STATCTRL 0x20
+
+#define VF610_DAC_DACEN BIT(15)
+#define VF610_DAC_DACRFS BIT(14)
+#define VF610_DAC_LPEN BIT(11)
+
+#define VF610_DAC_DAT0(x) ((x) & 0xFFF)
+
+enum vf610_conversion_mode_sel {
+ VF610_DAC_CONV_HIGH_POWER,
+ VF610_DAC_CONV_LOW_POWER,
+};
+
+struct vf610_dac {
+ struct clk *clk;
+ struct device *dev;
+ enum vf610_conversion_mode_sel conv_mode;
+ void __iomem *regs;
+};
+
+static void vf610_dac_init(struct vf610_dac *info)
+{
+ int val;
+
+ info->conv_mode = VF610_DAC_CONV_LOW_POWER;
+ val = VF610_DAC_DACEN | VF610_DAC_DACRFS |
+ VF610_DAC_LPEN;
+ writel(val, info->regs + VF610_DACx_STATCTRL);
+}
+
+static void vf610_dac_exit(struct vf610_dac *info)
+{
+ int val;
+
+ val = readl(info->regs + VF610_DACx_STATCTRL);
+ val &= ~VF610_DAC_DACEN;
+ writel(val, info->regs + VF610_DACx_STATCTRL);
+}
+
+static int vf610_set_conversion_mode(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ unsigned int mode)
+{
+ struct vf610_dac *info = iio_priv(indio_dev);
+ int val;
+
+ mutex_lock(&indio_dev->mlock);
+ info->conv_mode = mode;
+ val = readl(info->regs + VF610_DACx_STATCTRL);
+ if (mode)
+ val |= VF610_DAC_LPEN;
+ else
+ val &= ~VF610_DAC_LPEN;
+ writel(val, info->regs + VF610_DACx_STATCTRL);
+ mutex_unlock(&indio_dev->mlock);
+
+ return 0;
+}
+
+static int vf610_get_conversion_mode(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan)
+{
+ struct vf610_dac *info = iio_priv(indio_dev);
+
+ return info->conv_mode;
+}
+
+static const char * const vf610_conv_modes[] = { "high-power", "low-power" };
+
+static const struct iio_enum vf610_conversion_mode = {
+ .items = vf610_conv_modes,
+ .num_items = ARRAY_SIZE(vf610_conv_modes),
+ .get = vf610_get_conversion_mode,
+ .set = vf610_set_conversion_mode,
+};
+
+static const struct iio_chan_spec_ext_info vf610_ext_info[] = {
+ IIO_ENUM("conversion_mode", IIO_SHARED_BY_DIR,
+ &vf610_conversion_mode),
+ {},
+};
+
+#define VF610_DAC_CHAN(_chan_type) { \
+ .type = (_chan_type), \
+ .output = 1, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .ext_info = vf610_ext_info, \
+}
+
+static const struct iio_chan_spec vf610_dac_iio_channels[] = {
+ VF610_DAC_CHAN(IIO_VOLTAGE),
+};
+
+static int vf610_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2,
+ long mask)
+{
+ struct vf610_dac *info = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ *val = VF610_DAC_DAT0(readl(info->regs));
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ /*
+ * DACRFS is always 1 for valid reference and typical
+ * reference voltage as per Vybrid datasheet is 3.3V
+ * from section 9.1.2.1 of Vybrid datasheet
+ */
+ *val = 3300 /* mV */;
+ *val2 = 12;
+ return IIO_VAL_FRACTIONAL_LOG2;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int vf610_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2,
+ long mask)
+{
+ struct vf610_dac *info = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ mutex_lock(&indio_dev->mlock);
+ writel(VF610_DAC_DAT0(val), info->regs);
+ mutex_unlock(&indio_dev->mlock);
+ return 0;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct iio_info vf610_dac_iio_info = {
+ .driver_module = THIS_MODULE,
+ .read_raw = &vf610_read_raw,
+ .write_raw = &vf610_write_raw,
+};
+
+static const struct of_device_id vf610_dac_match[] = {
+ { .compatible = "fsl,vf610-dac", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, vf610_dac_match);
+
+static int vf610_dac_probe(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev;
+ struct vf610_dac *info;
+ struct resource *mem;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&pdev->dev,
+ sizeof(struct vf610_dac));
+ if (!indio_dev) {
+ dev_err(&pdev->dev, "Failed allocating iio device\n");
+ return -ENOMEM;
+ }
+
+ info = iio_priv(indio_dev);
+ info->dev = &pdev->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);
+
+ info->clk = devm_clk_get(&pdev->dev, "dac");
+ if (IS_ERR(info->clk)) {
+ dev_err(&pdev->dev, "Failed getting clock, err = %ld\n",
+ PTR_ERR(info->clk));
+ return PTR_ERR(info->clk);
+ }
+
+ 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 = &vf610_dac_iio_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = vf610_dac_iio_channels;
+ indio_dev->num_channels = ARRAY_SIZE(vf610_dac_iio_channels);
+
+ ret = clk_prepare_enable(info->clk);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "Could not prepare or enable the clock\n");
+ return ret;
+ }
+
+ vf610_dac_init(info);
+
+ ret = iio_device_register(indio_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "Couldn't register the device\n");
+ goto error_iio_device_register;
+ }
+
+ return 0;
+
+error_iio_device_register:
+ clk_disable_unprepare(info->clk);
+
+ return ret;
+}
+
+static int vf610_dac_remove(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+ struct vf610_dac *info = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+ vf610_dac_exit(info);
+ clk_disable_unprepare(info->clk);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int vf610_dac_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct vf610_dac *info = iio_priv(indio_dev);
+
+ vf610_dac_exit(info);
+ clk_disable_unprepare(info->clk);
+
+ return 0;
+}
+
+static int vf610_dac_resume(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct vf610_dac *info = iio_priv(indio_dev);
+ int ret;
+
+ ret = clk_prepare_enable(info->clk);
+ if (ret)
+ return ret;
+
+ vf610_dac_init(info);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(vf610_dac_pm_ops, vf610_dac_suspend, vf610_dac_resume);
+
+static struct platform_driver vf610_dac_driver = {
+ .probe = vf610_dac_probe,
+ .remove = vf610_dac_remove,
+ .driver = {
+ .name = "vf610-dac",
+ .of_match_table = vf610_dac_match,
+ .pm = &vf610_dac_pm_ops,
+ },
+};
+module_platform_driver(vf610_dac_driver);
+
+MODULE_AUTHOR("Sanchayan Maity <sanchayan.maity@toradex.com>");
+MODULE_DESCRIPTION("Freescale VF610 DAC driver");
+MODULE_LICENSE("GPL v2");