Re: [PATCHv4 4/4] hwmon: da9052: add support for TSI channel

Guenter Roeck
2017-06-30T15:56:11Z

On 06/30/2017 07:35 AM, Sebastian Reichel wrote:
> TSI channel has a 4 channel mux connected to it and is normally
> used for touchscreen support. The hardware may alternatively
> use it as general purpose adc.
>
> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
> ---
> drivers/hwmon/da9052-hwmon.c | 249 +++++++++++++++++++++++++++++++++++++-
> drivers/mfd/da9052-core.c | 28 ++++-
> include/linux/mfd/da9052/da9052.h | 6 +
> include/linux/mfd/da9052/reg.h | 11 +-

I just realized that you packed the hwmon and mfd changes into a single patch.
Please separate.

Thanks,
Guenter

> 4 files changed, 286 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/hwmon/da9052-hwmon.c b/drivers/hwmon/da9052-hwmon.c
> index 708c91ac601f..97a62f5b9ea4 100644
> --- a/drivers/hwmon/da9052-hwmon.c
> +++ b/drivers/hwmon/da9052-hwmon.c
> @@ -20,13 +20,19 @@
> #include <linux/module.h>
> #include <linux/slab.h>
> #include <linux/platform_device.h>
> +#include <linux/property.h>
>
> #include <linux/mfd/da9052/da9052.h>
> #include <linux/mfd/da9052/reg.h>
> +#include <linux/regulator/consumer.h>
>
> struct da9052_hwmon {
> - struct da9052 *da9052;
> - struct mutex hwmon_lock;
> + struct da9052 *da9052;
> + struct mutex hwmon_lock;
> + bool tsi_as_adc;
> + int tsiref_mv;
> + struct regulator *tsiref;
> + struct completion tsidone;
> };
>
> static const char * const input_names[] = {
> @@ -37,6 +43,10 @@ static const char * const input_names[] = {
> [DA9052_ADC_IN4] = "ADC IN4",
> [DA9052_ADC_IN5] = "ADC IN5",
> [DA9052_ADC_IN6] = "ADC IN6",
> + [DA9052_ADC_TSI_XP] = "ADC TS X+",
> + [DA9052_ADC_TSI_YP] = "ADC TS Y+",
> + [DA9052_ADC_TSI_XN] = "ADC TS X-",
> + [DA9052_ADC_TSI_YN] = "ADC TS Y-",
> [DA9052_ADC_TJUNC] = "BATTERY JUNCTION TEMP",
> [DA9052_ADC_VBBAT] = "BACK-UP BATTERY VOLTAGE",
> };
> @@ -59,6 +69,11 @@ static inline int vbbat_reg_to_mv(int value)
> return DIV_ROUND_CLOSEST(value * 5000, 1023);
> }
>
> +static inline int input_tsireg_to_mv(struct da9052_hwmon *hwmon, int value)
> +{
> + return DIV_ROUND_CLOSEST(value * hwmon->tsiref_mv, 1023);
> +}
> +
> static inline int da9052_enable_vddout_channel(struct da9052 *da9052)
> {
> return da9052_reg_update(da9052, DA9052_ADC_CONT_REG,
> @@ -154,6 +169,97 @@ static ssize_t da9052_read_misc_channel(struct device *dev,
> return sprintf(buf, "%d\n", input_reg_to_mv(ret));
> }
>
> +static int da9052_request_tsi_read(struct da9052_hwmon *hwmon, int channel)
> +{
> + u8 val = DA9052_TSICONTB_TSIMAN;
> +
> + switch (channel) {
> + case DA9052_ADC_TSI_XP:
> + val |= DA9052_TSICONTB_TSIMUX_XP;
> + break;
> + case DA9052_ADC_TSI_YP:
> + val |= DA9052_TSICONTB_TSIMUX_YP;
> + break;
> + case DA9052_ADC_TSI_XN:
> + val |= DA9052_TSICONTB_TSIMUX_XN;
> + break;
> + case DA9052_ADC_TSI_YN:
> + val |= DA9052_TSICONTB_TSIMUX_YN;
> + break;
> + }
> +
> + return da9052_reg_write(hwmon->da9052, DA9052_TSI_CONT_B_REG, val);
> +}
> +
> +static int da9052_get_tsi_result(struct da9052_hwmon *hwmon, int channel)
> +{
> + u8 regs[3];
> + int msb, lsb, err;
> +
> + /* block read to avoid separation of MSB and LSB */
> + err = da9052_group_read(hwmon->da9052, DA9052_TSI_X_MSB_REG,
> + ARRAY_SIZE(regs), regs);
> + if (err)
> + return err;
> +
> + switch (channel) {
> + case DA9052_ADC_TSI_XP:
> + case DA9052_ADC_TSI_XN:
> + msb = regs[0] << DA9052_TSILSB_TSIXL_BITS;
> + lsb = regs[2] & DA9052_TSILSB_TSIXL;
> + lsb >>= DA9052_TSILSB_TSIXL_SHIFT;
> + break;
> + case DA9052_ADC_TSI_YP:
> + case DA9052_ADC_TSI_YN:
> + msb = regs[1] << DA9052_TSILSB_TSIYL_BITS;
> + lsb = regs[2] & DA9052_TSILSB_TSIYL;
> + lsb >>= DA9052_TSILSB_TSIYL_SHIFT;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return msb | lsb;
> +}
> +
> +
> +static ssize_t __da9052_read_tsi(struct device *dev, int channel)
> +{
> + struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
> + int ret;
> +
> + reinit_completion(&hwmon->tsidone);
> +
> + ret = da9052_request_tsi_read(hwmon, channel);
> + if (ret < 0)
> + return ret;
> +
> + /* Wait for an conversion done interrupt */
> + if (!wait_for_completion_timeout(&hwmon->tsidone,
> + msecs_to_jiffies(500)))
> + return -ETIMEDOUT;
> +
> + return da9052_get_tsi_result(hwmon, channel);
> +}
> +
> +static ssize_t da9052_read_tsi(struct device *dev,
> + struct device_attribute *devattr,
> + char *buf)
> +{
> + struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
> + int channel = to_sensor_dev_attr(devattr)->index;
> + int ret;
> +
> + mutex_lock(&hwmon->hwmon_lock);
> + ret = __da9052_read_tsi(dev, channel);
> + mutex_unlock(&hwmon->hwmon_lock);
> +
> + if (ret < 0)
> + return ret;
> + else
> + return sprintf(buf, "%d\n", input_tsireg_to_mv(hwmon, ret));
> +}
> +
> static ssize_t da9052_read_tjunc(struct device *dev,
> struct device_attribute *devattr, char *buf)
> {
> @@ -196,6 +302,28 @@ static ssize_t show_label(struct device *dev,
> input_names[to_sensor_dev_attr(devattr)->index]);
> }
>
> +static umode_t da9052_channel_is_visible(struct kobject *kobj,
> + struct attribute *attr, int index)
> +{
> + struct device *dev = container_of(kobj, struct device, kobj);
> + struct da9052_hwmon *hwmon = dev_get_drvdata(dev);
> + struct device_attribute *dattr = container_of(attr,
> + struct device_attribute, attr);
> + struct sensor_device_attribute *sattr = to_sensor_dev_attr(dattr);
> +
> + if (!hwmon->tsi_as_adc) {
> + switch (sattr->index) {
> + case DA9052_ADC_TSI_XP:
> + case DA9052_ADC_TSI_YP:
> + case DA9052_ADC_TSI_XN:
> + case DA9052_ADC_TSI_YN:
> + return 0;
> + }
> + }
> +
> + return attr->mode;
> +}
> +
> static SENSOR_DEVICE_ATTR(in0_input, 0444, da9052_read_vddout, NULL,
> DA9052_ADC_VDDOUT);
> static SENSOR_DEVICE_ATTR(in0_label, 0444, show_label, NULL,
> @@ -221,6 +349,23 @@ static SENSOR_DEVICE_ATTR(in9_input, 0444, da9052_read_vbbat, NULL,
> static SENSOR_DEVICE_ATTR(in9_label, 0444, show_label, NULL,
> DA9052_ADC_VBBAT);
>
> +static SENSOR_DEVICE_ATTR(in70_input, 0444, da9052_read_tsi, NULL,
> + DA9052_ADC_TSI_XP);
> +static SENSOR_DEVICE_ATTR(in70_label, 0444, show_label, NULL,
> + DA9052_ADC_TSI_XP);
> +static SENSOR_DEVICE_ATTR(in71_input, 0444, da9052_read_tsi, NULL,
> + DA9052_ADC_TSI_XN);
> +static SENSOR_DEVICE_ATTR(in71_label, 0444, show_label, NULL,
> + DA9052_ADC_TSI_XN);
> +static SENSOR_DEVICE_ATTR(in72_input, 0444, da9052_read_tsi, NULL,
> + DA9052_ADC_TSI_YP);
> +static SENSOR_DEVICE_ATTR(in72_label, 0444, show_label, NULL,
> + DA9052_ADC_TSI_YP);
> +static SENSOR_DEVICE_ATTR(in73_input, 0444, da9052_read_tsi, NULL,
> + DA9052_ADC_TSI_YN);
> +static SENSOR_DEVICE_ATTR(in73_label, 0444, show_label, NULL,
> + DA9052_ADC_TSI_YN);
> +
> static SENSOR_DEVICE_ATTR(curr1_input, 0444, da9052_read_ich, NULL,
> DA9052_ADC_ICH);
> static SENSOR_DEVICE_ATTR(curr1_label, 0444, show_label, NULL,
> @@ -246,6 +391,14 @@ static struct attribute *da9052_attrs[] = {
> &sensor_dev_attr_in5_label.dev_attr.attr,
> &sensor_dev_attr_in6_input.dev_attr.attr,
> &sensor_dev_attr_in6_label.dev_attr.attr,
> + &sensor_dev_attr_in70_input.dev_attr.attr,
> + &sensor_dev_attr_in70_label.dev_attr.attr,
> + &sensor_dev_attr_in71_input.dev_attr.attr,
> + &sensor_dev_attr_in71_label.dev_attr.attr,
> + &sensor_dev_attr_in72_input.dev_attr.attr,
> + &sensor_dev_attr_in72_label.dev_attr.attr,
> + &sensor_dev_attr_in73_input.dev_attr.attr,
> + &sensor_dev_attr_in73_label.dev_attr.attr,
> &sensor_dev_attr_in9_input.dev_attr.attr,
> &sensor_dev_attr_in9_label.dev_attr.attr,
> &sensor_dev_attr_curr1_input.dev_attr.attr,
> @@ -257,29 +410,117 @@ static struct attribute *da9052_attrs[] = {
> NULL
> };
>
> -ATTRIBUTE_GROUPS(da9052);
> +static const struct attribute_group da9052_group = {
> + .attrs = da9052_attrs,
> + .is_visible = da9052_channel_is_visible,
> +};
> +__ATTRIBUTE_GROUPS(da9052);
> +
> +static irqreturn_t da9052_tsi_datardy_irq(int irq, void *data)
> +{
> + struct da9052_hwmon *hwmon = data;
> +
> + complete(&hwmon->tsidone);
> + return IRQ_HANDLED;
> +}
>
> static int da9052_hwmon_probe(struct platform_device *pdev)
> {
> struct device *dev = &pdev->dev;
> struct da9052_hwmon *hwmon;
> struct device *hwmon_dev;
> + int err;
>
> hwmon = devm_kzalloc(dev, sizeof(struct da9052_hwmon), GFP_KERNEL);
> if (!hwmon)
> return -ENOMEM;
>
> + platform_set_drvdata(pdev, hwmon);
> +
> mutex_init(&hwmon->hwmon_lock);
> hwmon->da9052 = dev_get_drvdata(pdev->dev.parent);
>
> + init_completion(&hwmon->tsidone);
> +
> + hwmon->tsi_as_adc =
> + device_property_read_bool(pdev->dev.parent, "dlg,tsi-as-adc");
> +
> + if (hwmon->tsi_as_adc) {
> + hwmon->tsiref = devm_regulator_get(pdev->dev.parent, "tsiref");
> + if (IS_ERR(hwmon->tsiref)) {
> + err = PTR_ERR(hwmon->tsiref);
> + dev_err(&pdev->dev, "failed to get tsiref: %d", err);
> + return err;
> + }
> +
> + err = regulator_enable(hwmon->tsiref);
> + if (err)
> + return err;
> +
> + hwmon->tsiref_mv = regulator_get_voltage(hwmon->tsiref);
> + if (hwmon->tsiref_mv < 0) {
> + err = hwmon->tsiref_mv;
> + goto exit_regulator;
> + }
> +
> + /* convert from microvolt (DT) to millivolt (hwmon) */
> + hwmon->tsiref_mv /= 1000;
> +
> + /* TSIREF limits from datasheet */
> + if (hwmon->tsiref_mv < 1800 || hwmon->tsiref_mv > 2600) {
> + dev_err(hwmon->da9052->dev, "invalid TSIREF voltage: %d",
> + hwmon->tsiref_mv);
> + err = -ENXIO;
> + goto exit_regulator;
> + }
> +
> + /* disable touchscreen features */
> + da9052_reg_write(hwmon->da9052, DA9052_TSI_CONT_A_REG, 0x00);
> +
> + err = da9052_request_irq(hwmon->da9052, DA9052_IRQ_TSIREADY,
> + "tsiready-irq", da9052_tsi_datardy_irq,
> + hwmon);
> + if (err) {
> + dev_err(&pdev->dev, "Failed to register TSIRDY IRQ: %d",
> + err);
> + goto exit_regulator;
> + }
> + }
> +
> hwmon_dev = devm_hwmon_device_register_with_groups(dev, "da9052",
> hwmon,
> da9052_groups);
> - return PTR_ERR_OR_ZERO(hwmon_dev);
> + err = PTR_ERR_OR_ZERO(hwmon_dev);
> + if (err)
> + goto exit_irq;
> +
> + return 0;
> +
> +exit_irq:
> + if (hwmon->tsi_as_adc)
> + da9052_free_irq(hwmon->da9052, DA9052_IRQ_TSIREADY, hwmon);
> +exit_regulator:
> + if (hwmon->tsiref)
> + regulator_disable(hwmon->tsiref);
> +
> + return err;
> +}
> +
> +static int da9052_hwmon_remove(struct platform_device *pdev)
> +{
> + struct da9052_hwmon *hwmon = platform_get_drvdata(pdev);
> +
> + if (hwmon->tsi_as_adc) {
> + da9052_free_irq(hwmon->da9052, DA9052_IRQ_TSIREADY, hwmon);
> + regulator_disable(hwmon->tsiref);
> + }
> +
> + return 0;
> }
>
> static struct platform_driver da9052_hwmon_driver = {
> .probe = da9052_hwmon_probe,
> + .remove = da9052_hwmon_remove,
> .driver = {
> .name = "da9052-hwmon",
> },
> diff --git a/drivers/mfd/da9052-core.c b/drivers/mfd/da9052-core.c
> index 977418ca9117..a671c18381d7 100644
> --- a/drivers/mfd/da9052-core.c
> +++ b/drivers/mfd/da9052-core.c
> @@ -18,6 +18,7 @@
> #include <linux/mfd/core.h>
> #include <linux/slab.h>
> #include <linux/module.h>
> +#include <linux/property.h>
>
> #include <linux/mfd/da9052/da9052.h>
> #include <linux/mfd/da9052/pdata.h>
> @@ -521,9 +522,6 @@ static const struct mfd_cell da9052_subdev_info[] = {
> .name = "da9052-wled3",
> },
> {
> - .name = "da9052-tsi",
> - },
> - {
> .name = "da9052-bat",
> },
> {
> @@ -531,6 +529,12 @@ static const struct mfd_cell da9052_subdev_info[] = {
> },
> };
>
> +static const struct mfd_cell da9052_tsi_subdev_info[] = {
> + {
> + .name = "da9052-tsi",
> + },
> +};
> +
> const struct regmap_config da9052_regmap_config = {
> .reg_bits = 8,
> .val_bits = 8,
> @@ -621,9 +625,27 @@ int da9052_device_init(struct da9052 *da9052, u8 chip_id)
> goto err;
> }
>
> + /*
> + * Check if touchscreen pins are used are analogue input instead
> + * of having a touchscreen connected to them. The analogue input
> + * functionality will be provided by hwmon driver (if enabled).
> + */
> + if (!device_property_read_bool(da9052->dev, "dlg,tsi-as-adc")) {
> + ret = mfd_add_devices(da9052->dev, PLATFORM_DEVID_AUTO,
> + da9052_tsi_subdev_info,
> + ARRAY_SIZE(da9052_tsi_subdev_info),
> + NULL, 0, NULL);
> + if (ret) {
> + dev_err(da9052->dev, "failed to add TSI subdev: %d\n",
> + ret);
> + goto err;
> + }
> + }
> +
> return 0;
>
> err:
> + mfd_remove_devices(da9052->dev);
> da9052_irq_exit(da9052);
>
> return ret;
> diff --git a/include/linux/mfd/da9052/da9052.h b/include/linux/mfd/da9052/da9052.h
> index ce9230af09c2..ae5b663836d0 100644
> --- a/include/linux/mfd/da9052/da9052.h
> +++ b/include/linux/mfd/da9052/da9052.h
> @@ -45,6 +45,12 @@
> #define DA9052_ADC_TJUNC 8
> #define DA9052_ADC_VBBAT 9
>
> +/* TSI channel has its own 4 channel mux */
> +#define DA9052_ADC_TSI_XP 70
> +#define DA9052_ADC_TSI_XN 71
> +#define DA9052_ADC_TSI_YP 72
> +#define DA9052_ADC_TSI_YN 73
> +
> #define DA9052_IRQ_DCIN 0
> #define DA9052_IRQ_VBUS 1
> #define DA9052_IRQ_DCINREM 2
> diff --git a/include/linux/mfd/da9052/reg.h b/include/linux/mfd/da9052/reg.h
> index 5010f978725c..76780ea8849c 100644
> --- a/include/linux/mfd/da9052/reg.h
> +++ b/include/linux/mfd/da9052/reg.h
> @@ -690,7 +690,10 @@
> /* TSI CONTROL REGISTER B BITS */
> #define DA9052_TSICONTB_ADCREF 0X80
> #define DA9052_TSICONTB_TSIMAN 0X40
> -#define DA9052_TSICONTB_TSIMUX 0X30
> +#define DA9052_TSICONTB_TSIMUX_XP 0X00
> +#define DA9052_TSICONTB_TSIMUX_YP 0X10
> +#define DA9052_TSICONTB_TSIMUX_XN 0X20
> +#define DA9052_TSICONTB_TSIMUX_YN 0X30
> #define DA9052_TSICONTB_TSISEL3 0X08
> #define DA9052_TSICONTB_TSISEL2 0X04
> #define DA9052_TSICONTB_TSISEL1 0X02
> @@ -705,8 +708,14 @@
> /* TSI CO-ORDINATE LSB RESULT REGISTER BITS */
> #define DA9052_TSILSB_PENDOWN 0X40
> #define DA9052_TSILSB_TSIZL 0X30
> +#define DA9052_TSILSB_TSIZL_SHIFT 4
> +#define DA9052_TSILSB_TSIZL_BITS 2
> #define DA9052_TSILSB_TSIYL 0X0C
> +#define DA9052_TSILSB_TSIYL_SHIFT 2
> +#define DA9052_TSILSB_TSIYL_BITS 2
> #define DA9052_TSILSB_TSIXL 0X03
> +#define DA9052_TSILSB_TSIXL_SHIFT 0
> +#define DA9052_TSILSB_TSIXL_BITS 2
>
> /* TSI Z MEASUREMENT MSB RESULT REGISTER BIT */
> #define DA9052_TSIZMSB_TSIZM 0XFF
>