[PATCH v2] regulator: wm831x: Convert to use GPIO descriptors

From: Linus Walleij
Date: Wed Jun 12 2019 - 03:47:04 EST


This converts the Wolfson Micro WM831x DCDC converter to use
a GPIO descriptor for the GPIO driving the DVS pin.

There is just one (non-DT) machine in the kernel using this, and
that is the Wolfson Micro (now Cirrus) Cragganmore 6410 so we
patch this board to pass a descriptor table and fix up the driver
accordingly.

Cc: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxx>
Cc: Richard Fitzgerald <rf@xxxxxxxxxxxxxxxxxxxxx>
Cc: patches@xxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
ChangeLog v1->v2:
- Use device name "wm831x-buckv.11" as described by Charles
- Use devm_gpiod_get() rather than the optional variant
---
arch/arm/mach-s3c64xx/mach-crag6410.c | 21 ++++++++++++++++++-
drivers/regulator/wm831x-dcdc.c | 29 ++++++++++++---------------
include/linux/mfd/wm831x/pdata.h | 1 -
3 files changed, 33 insertions(+), 18 deletions(-)

diff --git a/arch/arm/mach-s3c64xx/mach-crag6410.c b/arch/arm/mach-s3c64xx/mach-crag6410.c
index 379424d72ae7..8ec6a4f5eb05 100644
--- a/arch/arm/mach-s3c64xx/mach-crag6410.c
+++ b/arch/arm/mach-s3c64xx/mach-crag6410.c
@@ -15,6 +15,7 @@
#include <linux/io.h>
#include <linux/init.h>
#include <linux/gpio.h>
+#include <linux/gpio/machine.h>
#include <linux/leds.h>
#include <linux/delay.h>
#include <linux/mmc/host.h>
@@ -398,7 +399,6 @@ static struct pca953x_platform_data crag6410_pca_data = {
/* VDDARM is controlled by DVS1 connected to GPK(0) */
static struct wm831x_buckv_pdata vddarm_pdata = {
.dvs_control_src = 1,
- .dvs_gpio = S3C64XX_GPK(0),
};

static struct regulator_consumer_supply vddarm_consumers[] = {
@@ -596,6 +596,24 @@ static struct wm831x_pdata crag_pmic_pdata = {
.touch = &touch_pdata,
};

+/*
+ * VDDARM is eventually ending up as a regulator hanging on the MFD cell device
+ * "wm831x-buckv.1" spawn from drivers/mfd/wm831x-core.c.
+ *
+ * From the note on the platform data we can see that this is clearly DVS1
+ * and assigned as dcdc1 resource to the MFD core which sets .id of the cell
+ * spawning the DVS1 platform device to 1, then the cell platform device
+ * name is calculated from 10*instance + id resulting in the device name
+ * "wm831x-buckv.11"
+ */
+static struct gpiod_lookup_table crag_pmic_gpiod_table = {
+ .dev_id = "wm831x-buckv.11",
+ .table = {
+ GPIO_LOOKUP("GPIOK", 0, "dvs", GPIO_ACTIVE_HIGH),
+ { },
+ },
+};
+
static struct i2c_board_info i2c_devs0[] = {
{ I2C_BOARD_INFO("24c08", 0x50), },
{ I2C_BOARD_INFO("tca6408", 0x20),
@@ -836,6 +854,7 @@ static void __init crag6410_machine_init(void)
s3c_fb_set_platdata(&crag6410_lcd_pdata);
dwc2_hsotg_set_platdata(&crag6410_hsotg_pdata);

+ gpiod_add_lookup_table(&crag_pmic_gpiod_table);
i2c_register_board_info(0, i2c_devs0, ARRAY_SIZE(i2c_devs0));
i2c_register_board_info(1, i2c_devs1, ARRAY_SIZE(i2c_devs1));

diff --git a/drivers/regulator/wm831x-dcdc.c b/drivers/regulator/wm831x-dcdc.c
index b422eef97b77..018dbbd96771 100644
--- a/drivers/regulator/wm831x-dcdc.c
+++ b/drivers/regulator/wm831x-dcdc.c
@@ -15,7 +15,7 @@
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <linux/slab.h>

#include <linux/mfd/wm831x/core.h>
@@ -50,7 +50,7 @@ struct wm831x_dcdc {
int base;
struct wm831x *wm831x;
struct regulator_dev *regulator;
- int dvs_gpio;
+ struct gpio_desc *dvs_gpiod;
int dvs_gpio_state;
int on_vsel;
int dvs_vsel;
@@ -217,7 +217,7 @@ static int wm831x_buckv_set_dvs(struct regulator_dev *rdev, int state)
return 0;

dcdc->dvs_gpio_state = state;
- gpio_set_value(dcdc->dvs_gpio, state);
+ gpiod_set_value(dcdc->dvs_gpiod, state);

/* Should wait for DVS state change to be asserted if we have
* a GPIO for it, for now assume the device is configured
@@ -237,10 +237,10 @@ static int wm831x_buckv_set_voltage_sel(struct regulator_dev *rdev,
int ret;

/* If this value is already set then do a GPIO update if we can */
- if (dcdc->dvs_gpio && dcdc->on_vsel == vsel)
+ if (dcdc->dvs_gpiod && dcdc->on_vsel == vsel)
return wm831x_buckv_set_dvs(rdev, 0);

- if (dcdc->dvs_gpio && dcdc->dvs_vsel == vsel)
+ if (dcdc->dvs_gpiod && dcdc->dvs_vsel == vsel)
return wm831x_buckv_set_dvs(rdev, 1);

/* Always set the ON status to the minimum voltage */
@@ -249,7 +249,7 @@ static int wm831x_buckv_set_voltage_sel(struct regulator_dev *rdev,
return ret;
dcdc->on_vsel = vsel;

- if (!dcdc->dvs_gpio)
+ if (!dcdc->dvs_gpiod)
return ret;

/* Kick the voltage transition now */
@@ -296,7 +296,7 @@ static int wm831x_buckv_get_voltage_sel(struct regulator_dev *rdev)
{
struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);

- if (dcdc->dvs_gpio && dcdc->dvs_gpio_state)
+ if (dcdc->dvs_gpiod && dcdc->dvs_gpio_state)
return dcdc->dvs_vsel;
else
return dcdc->on_vsel;
@@ -337,7 +337,7 @@ static void wm831x_buckv_dvs_init(struct platform_device *pdev,
int ret;
u16 ctrl;

- if (!pdata || !pdata->dvs_gpio)
+ if (!pdata)
return;

/* gpiolib won't let us read the GPIO status so pick the higher
@@ -345,17 +345,14 @@ static void wm831x_buckv_dvs_init(struct platform_device *pdev,
*/
dcdc->dvs_gpio_state = pdata->dvs_init_state;

- ret = devm_gpio_request_one(&pdev->dev, pdata->dvs_gpio,
- dcdc->dvs_gpio_state ? GPIOF_INIT_HIGH : 0,
- "DCDC DVS");
- if (ret < 0) {
- dev_err(wm831x->dev, "Failed to get %s DVS GPIO: %d\n",
- dcdc->name, ret);
+ dcdc->dvs_gpiod = devm_gpiod_get(&pdev->dev, "dvs",
+ dcdc->dvs_gpio_state ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW);
+ if (IS_ERR(dcdc->dvs_gpiod)) {
+ dev_err(wm831x->dev, "Failed to get %s DVS GPIO: %ld\n",
+ dcdc->name, PTR_ERR(dcdc->dvs_gpiod));
return;
}

- dcdc->dvs_gpio = pdata->dvs_gpio;
-
switch (pdata->dvs_control_src) {
case 1:
ctrl = 2 << WM831X_DC1_DVS_SRC_SHIFT;
diff --git a/include/linux/mfd/wm831x/pdata.h b/include/linux/mfd/wm831x/pdata.h
index dcc9631b3052..1b8bb36e13b8 100644
--- a/include/linux/mfd/wm831x/pdata.h
+++ b/include/linux/mfd/wm831x/pdata.h
@@ -52,7 +52,6 @@ struct wm831x_battery_pdata {
* I2C or SPI buses.
*/
struct wm831x_buckv_pdata {
- int dvs_gpio; /** CPU GPIO to use for DVS switching */
int dvs_control_src; /** Hardware DVS source to use (1 or 2) */
int dvs_init_state; /** DVS state to expect on startup */
int dvs_state_gpio; /** CPU GPIO to use for monitoring status */
--
2.20.1