Commit 5eb39ef8 authored by Alexandre Belloni's avatar Alexandre Belloni Committed by Jonathan Cameron
Browse files

iio: adc: at91_adc: rework resolution selection 



Move the possible resolution values back to the driver. This removes the
atmel,adc-res and atmel,adc-res-names properties, leaving only
atmel,adc-use-res. As atmel,adc-res-names had to contain "lowres" and
"highres", those where already the only allowed values for
atmel,adc-use-res.

Also introduce a new compatible string for the sama5d3 as this is the only
one with a different resolution. Also it doesn't even have the LOWRES
bit.

Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: default avatarLudovic Desroches <ludovic.desroches@microchip.com>
Link: https://lore.kernel.org/r/20201128222818.1910764-3-alexandre.belloni@bootlin.com


Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent 197cefcd

drivers/iio/adc/at91_adc.c

+40 −57
Original line number Diff line number Diff line
@@ -204,6 +204,9 @@ struct at91_adc_caps { 
	u32 (*calc_startup_ticks)(u32 startup_time, u32 adc_clk_khz);



	u8	num_channels;



	u8	low_res_bits;

	u8	high_res_bits;

	struct at91_adc_reg_desc registers;

};
@@ -229,7 +232,6 @@ struct at91_adc_state { 
	bool			use_external;

	u32			vref_mv;

	u32			res;		/* resolution used for convertions */

	bool			low_res;	/* the resolution corresponds to the lowest one */

	wait_queue_head_t	wq_data_avail;

	const struct at91_adc_caps	*caps;
@@ -754,58 +756,6 @@ static int at91_adc_read_raw(struct iio_dev *idev, 
	return -EINVAL;

}



static int at91_adc_of_get_resolution(struct iio_dev *idev,

				      struct platform_device *pdev)

{

	struct at91_adc_state *st = iio_priv(idev);

	struct device_node *np = pdev->dev.of_node;

	int count, i, ret = 0;

	char *res_name, *s;

	u32 *resolutions;



	count = of_property_count_strings(np, "atmel,adc-res-names");

	if (count < 2) {

		dev_err(&idev->dev, "You must specified at least two resolution names for "

				    "adc-res-names property in the DT\n");

		return count;

	}



	resolutions = kmalloc_array(count, sizeof(*resolutions), GFP_KERNEL);

	if (!resolutions)

		return -ENOMEM;



	if (of_property_read_u32_array(np, "atmel,adc-res", resolutions, count)) {

		dev_err(&idev->dev, "Missing adc-res property in the DT.\n");

		ret = -ENODEV;

		goto ret;

	}



	if (of_property_read_string(np, "atmel,adc-use-res", (const char **)&res_name))

		res_name = "highres";



	for (i = 0; i < count; i++) {

		if (of_property_read_string_index(np, "atmel,adc-res-names", i, (const char **)&s))

			continue;



		if (strcmp(res_name, s))

			continue;



		st->res = resolutions[i];

		if (!strcmp(res_name, "lowres"))

			st->low_res = true;

		else

			st->low_res = false;



		dev_info(&idev->dev, "Resolution used: %u bits\n", st->res);

		goto ret;

	}



	dev_err(&idev->dev, "There is no resolution for %s\n", res_name);



ret:

	kfree(resolutions);

	return ret;

}



static u32 calc_startup_ticks_9260(u32 startup_time, u32 adc_clk_khz)

{
@@ -889,6 +839,7 @@ static int at91_adc_probe_dt(struct iio_dev *idev, 
	struct device_node *trig_node;

	int i = 0, ret;

	u32 prop;

	char *s;



	st->caps = of_device_get_match_data(&pdev->dev);
@@ -921,9 +872,13 @@ static int at91_adc_probe_dt(struct iio_dev *idev, 
	}

	st->vref_mv = prop;



	ret = at91_adc_of_get_resolution(idev, pdev);

	if (ret)

		goto error_ret;

	st->res = st->caps->high_res_bits;

	if (st->caps->low_res_bits &&

	    !of_property_read_string(node, "atmel,adc-use-res", (const char **)&s)

	    && !strcmp(s, "lowres"))

		st->res = st->caps->low_res_bits;



	dev_info(&idev->dev, "Resolution used: %u bits\n", st->res);



	st->registers = &st->caps->registers;

	st->num_channels = st->caps->num_channels;
@@ -1245,7 +1200,7 @@ static int at91_adc_probe(struct platform_device *pdev) 


	reg = AT91_ADC_PRESCAL_(prsc) & st->registers->mr_prescal_mask;

	reg |= AT91_ADC_STARTUP_(ticks) & st->registers->mr_startup_mask;

	if (st->low_res)

	if (st->res == st->caps->low_res_bits)

		reg |= AT91_ADC_LOWRES;

	if (st->sleep_mode)

		reg |= AT91_ADC_SLEEP;
@@ -1360,6 +1315,8 @@ static SIMPLE_DEV_PM_OPS(at91_adc_pm_ops, at91_adc_suspend, at91_adc_resume); 
static struct at91_adc_caps at91sam9260_caps = {

	.calc_startup_ticks = calc_startup_ticks_9260,

	.num_channels = 4,

	.low_res_bits = 8,

	.high_res_bits = 10,

	.registers = {

		.channel_base = AT91_ADC_CHR(0),

		.drdy_mask = AT91_ADC_DRDY,
@@ -1374,6 +1331,8 @@ static struct at91_adc_caps at91sam9rl_caps = { 
	.has_ts = true,

	.calc_startup_ticks = calc_startup_ticks_9260,	/* same as 9260 */

	.num_channels = 6,

	.low_res_bits = 8,

	.high_res_bits = 10,

	.registers = {

		.channel_base = AT91_ADC_CHR(0),

		.drdy_mask = AT91_ADC_DRDY,
@@ -1388,6 +1347,8 @@ static struct at91_adc_caps at91sam9g45_caps = { 
	.has_ts = true,

	.calc_startup_ticks = calc_startup_ticks_9260,	/* same as 9260 */

	.num_channels = 8,

	.low_res_bits = 8,

	.high_res_bits = 10,

	.registers = {

		.channel_base = AT91_ADC_CHR(0),

		.drdy_mask = AT91_ADC_DRDY,
@@ -1405,6 +1366,8 @@ static struct at91_adc_caps at91sam9x5_caps = { 
	.ts_pen_detect_sensitivity = 2,

	.calc_startup_ticks = calc_startup_ticks_9x5,

	.num_channels = 12,

	.low_res_bits = 8,

	.high_res_bits = 10,

	.registers = {

		.channel_base = AT91_ADC_CDR0_9X5,

		.drdy_mask = AT91_ADC_SR_DRDY_9X5,
@@ -1416,11 +1379,31 @@ static struct at91_adc_caps at91sam9x5_caps = { 
	},

};



static struct at91_adc_caps sama5d3_caps = {

	.has_ts = true,

	.has_tsmr = true,

	.ts_filter_average = 3,

	.ts_pen_detect_sensitivity = 2,

	.calc_startup_ticks = calc_startup_ticks_9x5,

	.num_channels = 12,

	.low_res_bits = 0,

	.high_res_bits = 12,

	.registers = {

		.channel_base = AT91_ADC_CDR0_9X5,

		.drdy_mask = AT91_ADC_SR_DRDY_9X5,

		.status_register = AT91_ADC_SR_9X5,

		.trigger_register = AT91_ADC_TRGR_9X5,

		.mr_prescal_mask = AT91_ADC_PRESCAL_9G45,

		.mr_startup_mask = AT91_ADC_STARTUP_9X5,

	},

};



static const struct of_device_id at91_adc_dt_ids[] = {

	{ .compatible = "atmel,at91sam9260-adc", .data = &at91sam9260_caps },

	{ .compatible = "atmel,at91sam9rl-adc", .data = &at91sam9rl_caps },

	{ .compatible = "atmel,at91sam9g45-adc", .data = &at91sam9g45_caps },

	{ .compatible = "atmel,at91sam9x5-adc", .data = &at91sam9x5_caps },

	{ .compatible = "atmel,sama5d3-adc", .data = &sama5d3_caps },

	{},

};

MODULE_DEVICE_TABLE(of, at91_adc_dt_ids);