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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Freescale Vybrid vf610 DAC driver4 *5 * Copyright 2016 Toradex AG6 */7 8#include <linux/clk.h>9#include <linux/err.h>10#include <linux/interrupt.h>11#include <linux/io.h>12#include <linux/kernel.h>13#include <linux/mod_devicetable.h>14#include <linux/module.h>15#include <linux/platform_device.h>16#include <linux/regulator/consumer.h>17#include <linux/slab.h>18 19#include <linux/iio/iio.h>20#include <linux/iio/sysfs.h>21 22#define VF610_DACx_STATCTRL 0x2023 24#define VF610_DAC_DACEN BIT(15)25#define VF610_DAC_DACRFS BIT(14)26#define VF610_DAC_LPEN BIT(11)27 28#define VF610_DAC_DAT0(x) ((x) & 0xFFF)29 30enum vf610_conversion_mode_sel {31 VF610_DAC_CONV_HIGH_POWER,32 VF610_DAC_CONV_LOW_POWER,33};34 35struct vf610_dac {36 struct clk *clk;37 struct device *dev;38 enum vf610_conversion_mode_sel conv_mode;39 void __iomem *regs;40 struct mutex lock;41};42 43static void vf610_dac_init(struct vf610_dac *info)44{45 int val;46 47 info->conv_mode = VF610_DAC_CONV_LOW_POWER;48 val = VF610_DAC_DACEN | VF610_DAC_DACRFS |49 VF610_DAC_LPEN;50 writel(val, info->regs + VF610_DACx_STATCTRL);51}52 53static void vf610_dac_exit(struct vf610_dac *info)54{55 int val;56 57 val = readl(info->regs + VF610_DACx_STATCTRL);58 val &= ~VF610_DAC_DACEN;59 writel(val, info->regs + VF610_DACx_STATCTRL);60}61 62static int vf610_set_conversion_mode(struct iio_dev *indio_dev,63 const struct iio_chan_spec *chan,64 unsigned int mode)65{66 struct vf610_dac *info = iio_priv(indio_dev);67 int val;68 69 mutex_lock(&info->lock);70 info->conv_mode = mode;71 val = readl(info->regs + VF610_DACx_STATCTRL);72 if (mode)73 val |= VF610_DAC_LPEN;74 else75 val &= ~VF610_DAC_LPEN;76 writel(val, info->regs + VF610_DACx_STATCTRL);77 mutex_unlock(&info->lock);78 79 return 0;80}81 82static int vf610_get_conversion_mode(struct iio_dev *indio_dev,83 const struct iio_chan_spec *chan)84{85 struct vf610_dac *info = iio_priv(indio_dev);86 87 return info->conv_mode;88}89 90static const char * const vf610_conv_modes[] = { "high-power", "low-power" };91 92static const struct iio_enum vf610_conversion_mode = {93 .items = vf610_conv_modes,94 .num_items = ARRAY_SIZE(vf610_conv_modes),95 .get = vf610_get_conversion_mode,96 .set = vf610_set_conversion_mode,97};98 99static const struct iio_chan_spec_ext_info vf610_ext_info[] = {100 IIO_ENUM("conversion_mode", IIO_SHARED_BY_DIR,101 &vf610_conversion_mode),102 {},103};104 105#define VF610_DAC_CHAN(_chan_type) { \106 .type = (_chan_type), \107 .output = 1, \108 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \109 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \110 .ext_info = vf610_ext_info, \111}112 113static const struct iio_chan_spec vf610_dac_iio_channels[] = {114 VF610_DAC_CHAN(IIO_VOLTAGE),115};116 117static int vf610_read_raw(struct iio_dev *indio_dev,118 struct iio_chan_spec const *chan,119 int *val, int *val2,120 long mask)121{122 struct vf610_dac *info = iio_priv(indio_dev);123 124 switch (mask) {125 case IIO_CHAN_INFO_RAW:126 *val = VF610_DAC_DAT0(readl(info->regs));127 return IIO_VAL_INT;128 case IIO_CHAN_INFO_SCALE:129 /*130 * DACRFS is always 1 for valid reference and typical131 * reference voltage as per Vybrid datasheet is 3.3V132 * from section 9.1.2.1 of Vybrid datasheet133 */134 *val = 3300 /* mV */;135 *val2 = 12;136 return IIO_VAL_FRACTIONAL_LOG2;137 138 default:139 return -EINVAL;140 }141}142 143static int vf610_write_raw(struct iio_dev *indio_dev,144 struct iio_chan_spec const *chan,145 int val, int val2,146 long mask)147{148 struct vf610_dac *info = iio_priv(indio_dev);149 150 switch (mask) {151 case IIO_CHAN_INFO_RAW:152 mutex_lock(&info->lock);153 writel(VF610_DAC_DAT0(val), info->regs);154 mutex_unlock(&info->lock);155 return 0;156 157 default:158 return -EINVAL;159 }160}161 162static const struct iio_info vf610_dac_iio_info = {163 .read_raw = &vf610_read_raw,164 .write_raw = &vf610_write_raw,165};166 167static const struct of_device_id vf610_dac_match[] = {168 { .compatible = "fsl,vf610-dac", },169 { /* sentinel */ }170};171MODULE_DEVICE_TABLE(of, vf610_dac_match);172 173static int vf610_dac_probe(struct platform_device *pdev)174{175 struct iio_dev *indio_dev;176 struct vf610_dac *info;177 int ret;178 179 indio_dev = devm_iio_device_alloc(&pdev->dev,180 sizeof(struct vf610_dac));181 if (!indio_dev) {182 dev_err(&pdev->dev, "Failed allocating iio device\n");183 return -ENOMEM;184 }185 186 info = iio_priv(indio_dev);187 info->dev = &pdev->dev;188 189 info->regs = devm_platform_ioremap_resource(pdev, 0);190 if (IS_ERR(info->regs))191 return PTR_ERR(info->regs);192 193 info->clk = devm_clk_get(&pdev->dev, "dac");194 if (IS_ERR(info->clk)) {195 dev_err(&pdev->dev, "Failed getting clock, err = %ld\n",196 PTR_ERR(info->clk));197 return PTR_ERR(info->clk);198 }199 200 platform_set_drvdata(pdev, indio_dev);201 202 indio_dev->name = dev_name(&pdev->dev);203 indio_dev->info = &vf610_dac_iio_info;204 indio_dev->modes = INDIO_DIRECT_MODE;205 indio_dev->channels = vf610_dac_iio_channels;206 indio_dev->num_channels = ARRAY_SIZE(vf610_dac_iio_channels);207 208 mutex_init(&info->lock);209 210 ret = clk_prepare_enable(info->clk);211 if (ret) {212 dev_err(&pdev->dev,213 "Could not prepare or enable the clock\n");214 return ret;215 }216 217 vf610_dac_init(info);218 219 ret = iio_device_register(indio_dev);220 if (ret) {221 dev_err(&pdev->dev, "Couldn't register the device\n");222 goto error_iio_device_register;223 }224 225 return 0;226 227error_iio_device_register:228 vf610_dac_exit(info);229 clk_disable_unprepare(info->clk);230 231 return ret;232}233 234static void vf610_dac_remove(struct platform_device *pdev)235{236 struct iio_dev *indio_dev = platform_get_drvdata(pdev);237 struct vf610_dac *info = iio_priv(indio_dev);238 239 iio_device_unregister(indio_dev);240 vf610_dac_exit(info);241 clk_disable_unprepare(info->clk);242}243 244static int vf610_dac_suspend(struct device *dev)245{246 struct iio_dev *indio_dev = dev_get_drvdata(dev);247 struct vf610_dac *info = iio_priv(indio_dev);248 249 vf610_dac_exit(info);250 clk_disable_unprepare(info->clk);251 252 return 0;253}254 255static int vf610_dac_resume(struct device *dev)256{257 struct iio_dev *indio_dev = dev_get_drvdata(dev);258 struct vf610_dac *info = iio_priv(indio_dev);259 int ret;260 261 ret = clk_prepare_enable(info->clk);262 if (ret)263 return ret;264 265 vf610_dac_init(info);266 267 return 0;268}269 270static DEFINE_SIMPLE_DEV_PM_OPS(vf610_dac_pm_ops, vf610_dac_suspend,271 vf610_dac_resume);272 273static struct platform_driver vf610_dac_driver = {274 .probe = vf610_dac_probe,275 .remove_new = vf610_dac_remove,276 .driver = {277 .name = "vf610-dac",278 .of_match_table = vf610_dac_match,279 .pm = pm_sleep_ptr(&vf610_dac_pm_ops),280 },281};282module_platform_driver(vf610_dac_driver);283 284MODULE_AUTHOR("Sanchayan Maity <sanchayan.maity@toradex.com>");285MODULE_DESCRIPTION("Freescale VF610 DAC driver");286MODULE_LICENSE("GPL v2");287