[PATCH 1/2] pmic: pca9450: Add optional SD_VSEL GPIO for LDO5

[PATCH 1/2] pmic: pca9450: Add optional SD_VSEL GPIO for LDO5

[Frieder Schrempf]

From: Frieder Schrempf <frieder.schrempf@kontron.de>

LDO5 has two separate control registers. LDO5CTRL_L is used if the
input signal SD_VSEL is low and LDO5CTRL_H if it is high.
The current driver implementation only uses LDO5CTRL_H. To make this
work on boards that have SD_VSEL connected to a GPIO, we add support
for specifying an optional GPIO and setting it to high at probe time.

In the future we might also want to add support for boards that have
SD_VSEL set to a fixed low level. In this case we need to change the
driver to be able to use the LDO5CTRL_L register.

This is a port of the same change in the Linux kernel:
8c67a11bae88 ("regulator: pca9450: Add SD_VSEL GPIO for LDO5")

Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
---
 drivers/power/pmic/pca9450.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/drivers/power/pmic/pca9450.c b/drivers/power/pmic/pca9450.c
index 116ac49a8db..6b9befba18c 100644
--- a/drivers/power/pmic/pca9450.c
+++ b/drivers/power/pmic/pca9450.c
@@ -7,9 +7,12 @@
 #include <fdtdec.h>
 #include <errno.h>
 #include <dm.h>
+#include <dm/device_compat.h>
 #include <i2c.h>
+#include <linux/err.h>
 #include <log.h>
 #include <asm/global_data.h>
+#include <asm-generic/gpio.h>
 #include <power/pmic.h>
 #include <power/regulator.h>
 #include <power/pca9450.h>
@@ -26,6 +29,10 @@ static const struct pmic_child_info pmic_children_info[] = {
 	{ },
 };
 
+struct pca9450_priv {
+	struct gpio_desc *sd_vsel_gpio;
+};
+
 static int pca9450_reg_count(struct udevice *dev)
 {
 	return PCA9450_REG_NUM;
@@ -76,6 +83,24 @@ static int pca9450_bind(struct udevice *dev)
 	return 0;
 }
 
+static int pca9450_probe(struct udevice *dev)
+{
+	struct pca9450_priv *priv = dev_get_priv(dev);
+	int ret = 0;
+
+	if (IS_ENABLED(CONFIG_DM_GPIO) && IS_ENABLED(CONFIG_DM_REGULATOR_PCA9450)) {
+		priv->sd_vsel_gpio = devm_gpiod_get_optional(dev, "sd-vsel",
+							     GPIOD_IS_OUT |
+							     GPIOD_IS_OUT_ACTIVE);
+		if (IS_ERR(priv->sd_vsel_gpio)) {
+			ret = PTR_ERR(priv->sd_vsel_gpio);
+			dev_err(dev, "Failed to request SD_VSEL GPIO: %d\n", ret);
+		}
+	}
+
+	return ret;
+}
+
 static struct dm_pmic_ops pca9450_ops = {
 	.reg_count = pca9450_reg_count,
 	.read = pca9450_read,
@@ -94,5 +119,7 @@ U_BOOT_DRIVER(pmic_pca9450) = {
 	.id = UCLASS_PMIC,
 	.of_match = pca9450_ids,
 	.bind = pca9450_bind,
+	.probe = pca9450_probe,
 	.ops = &pca9450_ops,
+	.priv_auto = sizeof(struct pca9450_priv),
 };
-- 
2.36.1

[PATCH 2/2] imx: kontron-sl-mx8mm: Enable PCA9450 regulator driver and fix SD card access

[Frieder Schrempf]

From: Frieder Schrempf <frieder.schrempf@kontron.de>

Currently accessing the SD card on USDHC2 fails with:

=> mmc dev 1
Card did not respond to voltage select! : -110

This is due to the fact that UHS modes are enabled in the defconfig
and the devicetree, but the referenced LDO5 regulator (reg_nvcc_sd)
is not available to switch the data lines from 3.3V to 1.8V mode.

By enabling the regulator driver the vqmmc-supply is now available
and the SD card works also in high speed modes:

=> mmc dev 1
switch to partitions #0, OK
mmc1 is current device

Please note that the board has a GPIO connected to the SD_VSEL signal
of the PMIC. As the driver uses the LDO5CTRL_H register to set the
voltage, we need to make sure that this GPIO (GPIO01_IO4) is set to
a high level.

Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
---
Hi Tom, sorry for another late fix. I just keep discovering things
that are broken.

Please note that this depends on a driver change in patch 1 of this
series.
---
 configs/kontron-sl-mx8mm_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/configs/kontron-sl-mx8mm_defconfig b/configs/kontron-sl-mx8mm_defconfig
index 2e9d52522b2..727f99f0063 100644
--- a/configs/kontron-sl-mx8mm_defconfig
+++ b/configs/kontron-sl-mx8mm_defconfig
@@ -99,6 +99,7 @@ CONFIG_DM_PMIC=y
 CONFIG_DM_PMIC_PCA9450=y
 CONFIG_SPL_DM_PMIC_PCA9450=y
 CONFIG_DM_REGULATOR=y
+CONFIG_DM_REGULATOR_PCA9450=y
 CONFIG_DM_RTC=y
 CONFIG_RTC_RV8803=y
 CONFIG_CONS_INDEX=2
-- 
2.36.1

Re: [PATCH 1/2] pmic: pca9450: Add optional SD_VSEL GPIO for LDO5

[Fabio Estevam]

On 23/06/2022 14:42, Frieder Schrempf wrote:
> From: Frieder Schrempf <frieder.schrempf@kontron.de>
> 
> LDO5 has two separate control registers. LDO5CTRL_L is used if the
> input signal SD_VSEL is low and LDO5CTRL_H if it is high.
> The current driver implementation only uses LDO5CTRL_H. To make this
> work on boards that have SD_VSEL connected to a GPIO, we add support
> for specifying an optional GPIO and setting it to high at probe time.
> 
> In the future we might also want to add support for boards that have
> SD_VSEL set to a fixed low level. In this case we need to change the
> driver to be able to use the LDO5CTRL_L register.
> 
> This is a port of the same change in the Linux kernel:
> 8c67a11bae88 ("regulator: pca9450: Add SD_VSEL GPIO for LDO5")
> 
> Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>

Reviewed-by: Fabio Estevam <festevam@denx.de>

Re: [PATCH 2/2] imx: kontron-sl-mx8mm: Enable PCA9450 regulator driver and fix SD card access

[Fabio Estevam]

On 23/06/2022 14:42, Frieder Schrempf wrote:
> From: Frieder Schrempf <frieder.schrempf@kontron.de>
> 
> Currently accessing the SD card on USDHC2 fails with:
> 
> => mmc dev 1
> Card did not respond to voltage select! : -110
> 
> This is due to the fact that UHS modes are enabled in the defconfig
> and the devicetree, but the referenced LDO5 regulator (reg_nvcc_sd)
> is not available to switch the data lines from 3.3V to 1.8V mode.
> 
> By enabling the regulator driver the vqmmc-supply is now available
> and the SD card works also in high speed modes:
> 
> => mmc dev 1
> switch to partitions #0, OK
> mmc1 is current device
> 
> Please note that the board has a GPIO connected to the SD_VSEL signal
> of the PMIC. As the driver uses the LDO5CTRL_H register to set the
> voltage, we need to make sure that this GPIO (GPIO01_IO4) is set to
> a high level.
> 
> Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>

Reviewed-by: Fabio Estevam <festevam@denx.de>