Re: [PATCH V2 4/7] iio: adc: sc27xx: add support for PMIC sc2720 and sc2721

From: Baolin Wang
Date: Wed Mar 23 2022 - 10:05:43 EST

On Sat, Mar 12, 2022 at 12:47 AM Cixi Geng <gengcixi@xxxxxxxxx> wrote:
>
> From: Cixi Geng <cixi.geng1@xxxxxxxxxx>
>
> sc2720 and sc2721 is the product of sc27xx series.
>
> Signed-off-by: Yuming Zhu <yuming.zhu1@xxxxxxxxxx>
> Signed-off-by: Cixi Geng <cixi.geng1@xxxxxxxxxx>
>
> v2 changes:
>
> 1. modify code by the baolin's comment
>
> Reviewed-by: Baolin Wang <baolin.wang7@xxxxxxxxx>

I think I did not add a reviewed-by tag for this patch before, please drop it.

>
> 2.fix smatch warnings in sc27xx_adc_read()
>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> ---
> drivers/iio/adc/sc27xx_adc.c | 201 ++++++++++++++++++++++++++++++++++-
> 1 file changed, 200 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iio/adc/sc27xx_adc.c b/drivers/iio/adc/sc27xx_adc.c
> index 68629fbcfec5..2603ce313b07 100644
> --- a/drivers/iio/adc/sc27xx_adc.c
> +++ b/drivers/iio/adc/sc27xx_adc.c
> @@ -9,11 +9,13 @@
> #include <linux/of_device.h>
> #include <linux/platform_device.h>
> #include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
> #include <linux/slab.h>
>
> /* PMIC global registers definition */
> #define SC2731_MODULE_EN 0xc08
> #define SC27XX_MODULE_ADC_EN BIT(5)
> +#define SC2721_ARM_CLK_EN 0xc0c
> #define SC2731_ARM_CLK_EN 0xc10
> #define SC27XX_CLK_ADC_EN BIT(5)
> #define SC27XX_CLK_ADC_CLK_EN BIT(6)
> @@ -37,7 +39,9 @@
> /* Bits and mask definition for SC27XX_ADC_CH_CFG register */
> #define SC27XX_ADC_CHN_ID_MASK GENMASK(4, 0)
> #define SC27XX_ADC_SCALE_MASK GENMASK(10, 9)
> +#define SC2721_ADC_SCALE_MASK BIT(5)
> #define SC27XX_ADC_SCALE_SHIFT 9
> +#define SC2721_ADC_SCALE_SHIFT 5
>
> /* Bits definitions for SC27XX_ADC_INT_EN registers */
> #define SC27XX_ADC_IRQ_EN BIT(0)
> @@ -67,8 +71,20 @@
> #define SC27XX_RATIO_NUMERATOR_OFFSET 16
> #define SC27XX_RATIO_DENOMINATOR_MASK GENMASK(15, 0)
>
> +/* ADC specific channel reference voltage 3.5V */
> +#define SC27XX_ADC_REFVOL_VDD35 3500000
> +
> +/* ADC default channel reference voltage is 2.8V */
> +#define SC27XX_ADC_REFVOL_VDD28 2800000
> +
> +enum sc27xx_pmic_type {
> + SC27XX_ADC,
> + SC2721_ADC,
> +};
> +
> struct sc27xx_adc_data {
> struct device *dev;
> + struct regulator *volref;
> struct regmap *regmap;
> /*
> * One hardware spinlock to synchronize between the multiple
> @@ -87,6 +103,7 @@ struct sc27xx_adc_data {
> * in the device data structure.
> */
> struct sc27xx_adc_variant_data {
> + enum sc27xx_pmic_type pmic_type;
> u32 module_en;
> u32 clk_en;
> u32 scale_shift;
> @@ -188,6 +205,94 @@ static int sc27xx_adc_scale_calibration(struct sc27xx_adc_data *data,
> return 0;
> }
>
> +static int sc2720_adc_get_ratio(int channel, int scale)
> +{
> + switch (channel) {
> + case 14:
> + switch (scale) {
> + case 0:
> + return SC27XX_VOLT_RATIO(68, 900);
> + case 1:
> + return SC27XX_VOLT_RATIO(68, 1760);
> + case 2:
> + return SC27XX_VOLT_RATIO(68, 2327);
> + case 3:
> + return SC27XX_VOLT_RATIO(68, 3654);
> + default:
> + return SC27XX_VOLT_RATIO(1, 1);
> + }
> + case 16:
> + switch (scale) {
> + case 0:
> + return SC27XX_VOLT_RATIO(48, 100);
> + case 1:
> + return SC27XX_VOLT_RATIO(480, 1955);
> + case 2:
> + return SC27XX_VOLT_RATIO(480, 2586);
> + case 3:
> + return SC27XX_VOLT_RATIO(48, 406);
> + default:
> + return SC27XX_VOLT_RATIO(1, 1);
> + }
> + case 21:
> + case 22:
> + case 23:
> + switch (scale) {
> + case 0:
> + return SC27XX_VOLT_RATIO(3, 8);
> + case 1:
> + return SC27XX_VOLT_RATIO(375, 1955);
> + case 2:
> + return SC27XX_VOLT_RATIO(375, 2586);
> + case 3:
> + return SC27XX_VOLT_RATIO(300, 3248);
> + default:
> + return SC27XX_VOLT_RATIO(1, 1);
> + }
> + default:
> + switch (scale) {
> + case 0:
> + return SC27XX_VOLT_RATIO(1, 1);
> + case 1:
> + return SC27XX_VOLT_RATIO(1000, 1955);
> + case 2:
> + return SC27XX_VOLT_RATIO(1000, 2586);
> + case 3:
> + return SC27XX_VOLT_RATIO(100, 406);
> + default:
> + return SC27XX_VOLT_RATIO(1, 1);
> + }
> + }
> + return SC27XX_VOLT_RATIO(1, 1);
> +}
> +
> +static int sc2721_adc_get_ratio(int channel, int scale)
> +{
> + switch (channel) {
> + case 1:
> + case 2:
> + case 3:
> + case 4:
> + return scale ? SC27XX_VOLT_RATIO(400, 1025) :
> + SC27XX_VOLT_RATIO(1, 1);
> + case 5:
> + return SC27XX_VOLT_RATIO(7, 29);
> + case 7:
> + case 9:
> + return scale ? SC27XX_VOLT_RATIO(100, 125) :
> + SC27XX_VOLT_RATIO(1, 1);
> + case 14:
> + return SC27XX_VOLT_RATIO(68, 900);
> + case 16:
> + return SC27XX_VOLT_RATIO(48, 100);
> + case 19:
> + return SC27XX_VOLT_RATIO(1, 3);
> + default:
> + return SC27XX_VOLT_RATIO(1, 1);
> + }
> + return SC27XX_VOLT_RATIO(1, 1);
> +}
> +
> static int sc2731_adc_get_ratio(int channel, int scale)
> {
> switch (channel) {
> @@ -216,6 +321,34 @@ static int sc2731_adc_get_ratio(int channel, int scale)
> /*
> * According to the datasheet set specific value on some channel.
> */
> +static void sc2720_adc_scale_init(struct sc27xx_adc_data *data)
> +{
> + int i;
> +
> + for (i = 0; i < SC27XX_ADC_CHANNEL_MAX; i++) {
> + switch (i) {
> + case 5:
> + data->channel_scale[i] = 3;
> + break;
> + case 7:
> + case 9:
> + data->channel_scale[i] = 2;
> + break;
> + case 13:
> + data->channel_scale[i] = 1;
> + break;
> + case 19:
> + case 30:
> + case 31:
> + data->channel_scale[i] = 3;
> + break;
> + default:
> + data->channel_scale[i] = 0;
> + break;
> + }
> + }
> +}
> +
> static void sc2731_adc_scale_init(struct sc27xx_adc_data *data)
> {
> int i;
> @@ -231,7 +364,7 @@ static void sc2731_adc_scale_init(struct sc27xx_adc_data *data)
> static int sc27xx_adc_read(struct sc27xx_adc_data *data, int channel,
> int scale, int *val)
> {
> - int ret;
> + int ret, ret_volref;
> u32 tmp, value, status;
>
> ret = hwspin_lock_timeout_raw(data->hwlock, SC27XX_ADC_HWLOCK_TIMEOUT);
> @@ -240,6 +373,22 @@ static int sc27xx_adc_read(struct sc27xx_adc_data *data, int channel,
> return ret;
> }
>
> + /*
> + * According to the sc2721 chip data sheet, the reference voltage of
> + * specific channel 30 and channel 31 in ADC module needs to be set from
> + * the default 2.8v to 3.5v.
> + */
> + if ((data->var_data->pmic_type == SC2721_ADC) && (channel == 30 || channel == 31)) {
> + ret = regulator_set_voltage(data->volref,
> + SC27XX_ADC_REFVOL_VDD35,
> + SC27XX_ADC_REFVOL_VDD35);
> + if (ret) {
> + dev_err(data->dev, "failed to set the volref 3.5V\n");
> + hwspin_unlock_raw(data->hwlock);

Please remove duplicate code, just "goto unlock_adc". Then add a new
label like "regultor_restore" to restore the regulator in the error
path.

> + return ret;
> + }
> + }
> +
> ret = regmap_update_bits(data->regmap, data->base + SC27XX_ADC_CTL,
> SC27XX_ADC_EN, SC27XX_ADC_EN);
> if (ret)
> @@ -294,6 +443,18 @@ static int sc27xx_adc_read(struct sc27xx_adc_data *data, int channel,
> regmap_update_bits(data->regmap, data->base + SC27XX_ADC_CTL,
> SC27XX_ADC_EN, 0);
> unlock_adc:
> + if (data->var_data->pmic_type == SC2721_ADC) {
> + if ((channel == 30) || (channel == 31)) {
> + ret_volref = regulator_set_voltage(data->volref,
> + SC27XX_ADC_REFVOL_VDD28,
> + SC27XX_ADC_REFVOL_VDD28);
> + if (ret_volref) {
> + dev_err(data->dev, "failed to set the volref 2.8V, ret_volref = 0x%x\n,ret_volref");
> + ret = ret || ret_volref;
> + }
> + }
> + }
> +
> hwspin_unlock_raw(data->hwlock);
>
> if (!ret)
> @@ -523,6 +684,7 @@ static void sc27xx_adc_disable(void *_data)
> }
>



--
Baolin Wang