[PATCH v2 2/2] iio: adc: modify NPCM reset support

From: Tomer Maimon
Date: Mon Feb 03 2020 - 10:10:31 EST


Modify NPCM ADC reset support from
direct register access to reset controller support.

please make sure to modify NPCM adc device tree
parameters as described at nuvoton,npcm-adc.txt
document for using this change.

Signed-off-by: Tomer Maimon <tmaimon77@xxxxxxxxx>
---
drivers/iio/adc/npcm_adc.c | 30 +++++++++---------------------
1 file changed, 9 insertions(+), 21 deletions(-)

diff --git a/drivers/iio/adc/npcm_adc.c b/drivers/iio/adc/npcm_adc.c
index a6170a37ebe8..83bad2d5575d 100644
--- a/drivers/iio/adc/npcm_adc.c
+++ b/drivers/iio/adc/npcm_adc.c
@@ -14,6 +14,7 @@
#include <linux/regulator/consumer.h>
#include <linux/spinlock.h>
#include <linux/uaccess.h>
+#include <linux/reset.h>

struct npcm_adc {
bool int_status;
@@ -23,13 +24,9 @@ struct npcm_adc {
struct clk *adc_clk;
wait_queue_head_t wq;
struct regulator *vref;
- struct regmap *rst_regmap;
+ struct reset_control *reset;
};

-/* NPCM7xx reset module */
-#define NPCM7XX_IPSRST1_OFFSET 0x020
-#define NPCM7XX_IPSRST1_ADC_RST BIT(27)
-
/* ADC registers */
#define NPCM_ADCCON 0x00
#define NPCM_ADCDATA 0x04
@@ -106,13 +103,11 @@ static int npcm_adc_read(struct npcm_adc *info, int *val, u8 channel)
msecs_to_jiffies(10));
if (ret == 0) {
regtemp = ioread32(info->regs + NPCM_ADCCON);
- if ((regtemp & NPCM_ADCCON_ADC_CONV) && info->rst_regmap) {
+ if (regtemp & NPCM_ADCCON_ADC_CONV) {
/* if conversion failed - reset ADC module */
- regmap_write(info->rst_regmap, NPCM7XX_IPSRST1_OFFSET,
- NPCM7XX_IPSRST1_ADC_RST);
+ reset_control_assert(info->reset);
msleep(100);
- regmap_write(info->rst_regmap, NPCM7XX_IPSRST1_OFFSET,
- 0x0);
+ reset_control_deassert(info->reset);
msleep(100);

/* Enable ADC and start conversion module */
@@ -186,7 +181,6 @@ static int npcm_adc_probe(struct platform_device *pdev)
struct npcm_adc *info;
struct iio_dev *indio_dev;
struct device *dev = &pdev->dev;
- struct device_node *np = pdev->dev.of_node;

indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
if (!indio_dev)
@@ -199,6 +193,10 @@ static int npcm_adc_probe(struct platform_device *pdev)
if (IS_ERR(info->regs))
return PTR_ERR(info->regs);

+ info->reset = devm_reset_control_get(&pdev->dev, NULL);
+ if (IS_ERR(info->reset))
+ return PTR_ERR(info->reset);
+
info->adc_clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(info->adc_clk)) {
dev_warn(&pdev->dev, "ADC clock failed: can't read clk\n");
@@ -211,16 +209,6 @@ static int npcm_adc_probe(struct platform_device *pdev)
div = div >> NPCM_ADCCON_DIV_SHIFT;
info->adc_sample_hz = clk_get_rate(info->adc_clk) / ((div + 1) * 2);

- if (of_device_is_compatible(np, "nuvoton,npcm750-adc")) {
- info->rst_regmap = syscon_regmap_lookup_by_compatible
- ("nuvoton,npcm750-rst");
- if (IS_ERR(info->rst_regmap)) {
- dev_err(&pdev->dev, "Failed to find nuvoton,npcm750-rst\n");
- ret = PTR_ERR(info->rst_regmap);
- goto err_disable_clk;
- }
- }
-
irq = platform_get_irq(pdev, 0);
if (irq <= 0) {
ret = -EINVAL;
--
2.22.0