[PATCH v5 0/3] mmc: atmel-mci: Convert to gpio descriptors

[PATCH v5 0/3] mmc: atmel-mci: Convert to gpio descriptors

[Balamanikandan Gunasundar]

Replace legacy gpio apis with gpio descriptors. Handle card detection gpio
polarity in gpiolib

v5:
- Rebase to latest next branch of
  https://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc.git
- Move handling active_high inversion logic to gpiolib instead of reading
  the raw value of gpio and inverting it manually.
- Use PTR_ERR_OR_ZERO instead of IS_ERR. To avoid ignoring valid errors as
  suggested by Dmitry Torokhov
- Use gpiod_get_value_cansleep() instead of gpiod_get_value()

v4:
- Rebase on top of next branch
  https://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc.git 

v3:
- [PATCH v3 1/2] mmc: atmel-mci: Convert to gpio descriptors
  Convert devm_gpiod_get_from_of_node() into devm_fwnode_gpiod_get()

v2:
- [PATCH 1/2] mmc: atmel-mci: Convert to gpio descriptors
  Remove "#include <linux/gpio.h>" as it is not necessary
- [PATCH 2/2] mmc: atmel-mci: move atmel MCI header file
  Move linux/atmel-mci.h into drivers/mmc/host/atmel-mci.c as it is
  used only by one file


Balamanikandan Gunasundar (3):
  mmc: atmel-mci: Convert to gpio descriptors
  mmc: atmel-mci: move atmel MCI header file
  mmc: atmel-mci: Move card detect gpio polarity quirk to gpiolib

 drivers/gpio/gpiolib-of.c    |   7 ++
 drivers/mmc/host/atmel-mci.c | 133 +++++++++++++++++++++--------------
 include/linux/atmel-mci.h    |  46 ------------
 3 files changed, 89 insertions(+), 97 deletions(-)
 delete mode 100644 include/linux/atmel-mci.h

-- 
2.25.1

[PATCH v5 1/3] mmc: atmel-mci: Convert to gpio descriptors

[Balamanikandan Gunasundar]

Replace the legacy GPIO APIs with gpio descriptor consumer interface.
To maintain backward compatibility, we rely on the "cd-inverted"
property to manage the invertion flag instead of GPIO property.

Signed-off-by: Balamanikandan Gunasundar <balamanikandan.gunasundar@microchip.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
---
 drivers/mmc/host/atmel-mci.c | 77 +++++++++++++++++-------------------
 include/linux/atmel-mci.h    |  4 +-
 2 files changed, 39 insertions(+), 42 deletions(-)

diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index 1f89d02c4685..892d29fed9ec 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -11,14 +11,14 @@
 #include <linux/dmaengine.h>
 #include <linux/dma-mapping.h>
 #include <linux/err.h>
-#include <linux/gpio.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/ioport.h>
 #include <linux/module.h>
 #include <linux/of.h>
-#include <linux/of_gpio.h>
+#include <linux/irq.h>
+#include <linux/gpio/consumer.h>
 #include <linux/platform_device.h>
 #include <linux/scatterlist.h>
 #include <linux/seq_file.h>
@@ -387,8 +387,8 @@ struct atmel_mci_slot {
 #define ATMCI_CARD_NEED_INIT	1
 #define ATMCI_SHUTDOWN		2
 
-	int			detect_pin;
-	int			wp_pin;
+	struct gpio_desc        *detect_pin;
+	struct gpio_desc	*wp_pin;
 	bool			detect_is_active_high;
 
 	struct timer_list	detect_timer;
@@ -636,7 +636,10 @@ atmci_of_init(struct platform_device *pdev)
 			pdata->slot[slot_id].bus_width = 1;
 
 		pdata->slot[slot_id].detect_pin =
-			of_get_named_gpio(cnp, "cd-gpios", 0);
+			devm_fwnode_gpiod_get(&pdev->dev, of_fwnode_handle(cnp),
+					      "cd", GPIOD_IN, "cd-gpios");
+		if (IS_ERR(pdata->slot[slot_id].detect_pin))
+			pdata->slot[slot_id].detect_pin = NULL;
 
 		pdata->slot[slot_id].detect_is_active_high =
 			of_property_read_bool(cnp, "cd-inverted");
@@ -645,7 +648,10 @@ atmci_of_init(struct platform_device *pdev)
 			of_property_read_bool(cnp, "non-removable");
 
 		pdata->slot[slot_id].wp_pin =
-			of_get_named_gpio(cnp, "wp-gpios", 0);
+			devm_fwnode_gpiod_get(&pdev->dev, of_fwnode_handle(cnp),
+					      "wp", GPIOD_IN, "wp-gpios");
+		if (IS_ERR(pdata->slot[slot_id].wp_pin))
+			pdata->slot[slot_id].wp_pin = NULL;
 	}
 
 	return pdata;
@@ -1508,8 +1514,8 @@ static int atmci_get_ro(struct mmc_host *mmc)
 	int			read_only = -ENOSYS;
 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
 
-	if (gpio_is_valid(slot->wp_pin)) {
-		read_only = gpio_get_value(slot->wp_pin);
+	if (slot->wp_pin) {
+		read_only = gpiod_get_value(slot->wp_pin);
 		dev_dbg(&mmc->class_dev, "card is %s\n",
 				read_only ? "read-only" : "read-write");
 	}
@@ -1522,8 +1528,8 @@ static int atmci_get_cd(struct mmc_host *mmc)
 	int			present = -ENOSYS;
 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
 
-	if (gpio_is_valid(slot->detect_pin)) {
-		present = !(gpio_get_value(slot->detect_pin) ^
+	if (slot->detect_pin) {
+		present = !(gpiod_get_raw_value(slot->detect_pin) ^
 			    slot->detect_is_active_high);
 		dev_dbg(&mmc->class_dev, "card is %spresent\n",
 				present ? "" : "not ");
@@ -1636,8 +1642,8 @@ static void atmci_detect_change(struct timer_list *t)
 	if (test_bit(ATMCI_SHUTDOWN, &slot->flags))
 		return;
 
-	enable_irq(gpio_to_irq(slot->detect_pin));
-	present = !(gpio_get_value(slot->detect_pin) ^
+	enable_irq(gpiod_to_irq(slot->detect_pin));
+	present = !(gpiod_get_raw_value(slot->detect_pin) ^
 		    slot->detect_is_active_high);
 	present_old = test_bit(ATMCI_CARD_PRESENT, &slot->flags);
 
@@ -2236,9 +2242,9 @@ static int atmci_init_slot(struct atmel_mci *host,
 	dev_dbg(&mmc->class_dev,
 	        "slot[%u]: bus_width=%u, detect_pin=%d, "
 		"detect_is_active_high=%s, wp_pin=%d\n",
-		id, slot_data->bus_width, slot_data->detect_pin,
+		id, slot_data->bus_width, desc_to_gpio(slot_data->detect_pin),
 		slot_data->detect_is_active_high ? "true" : "false",
-		slot_data->wp_pin);
+		desc_to_gpio(slot_data->wp_pin));
 
 	mmc->ops = &atmci_ops;
 	mmc->f_min = DIV_ROUND_UP(host->bus_hz, 512);
@@ -2274,31 +2280,24 @@ static int atmci_init_slot(struct atmel_mci *host,
 
 	/* Assume card is present initially */
 	set_bit(ATMCI_CARD_PRESENT, &slot->flags);
-	if (gpio_is_valid(slot->detect_pin)) {
-		if (devm_gpio_request(&host->pdev->dev, slot->detect_pin,
-				      "mmc_detect")) {
-			dev_dbg(&mmc->class_dev, "no detect pin available\n");
-			slot->detect_pin = -EBUSY;
-		} else if (gpio_get_value(slot->detect_pin) ^
-				slot->detect_is_active_high) {
+	if (slot->detect_pin) {
+		if (gpiod_get_raw_value(slot->detect_pin) ^
+		    slot->detect_is_active_high) {
 			clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
 		}
+	} else {
+		dev_dbg(&mmc->class_dev, "no detect pin available\n");
 	}
 
-	if (!gpio_is_valid(slot->detect_pin)) {
+	if (!slot->detect_pin) {
 		if (slot_data->non_removable)
 			mmc->caps |= MMC_CAP_NONREMOVABLE;
 		else
 			mmc->caps |= MMC_CAP_NEEDS_POLL;
 	}
 
-	if (gpio_is_valid(slot->wp_pin)) {
-		if (devm_gpio_request(&host->pdev->dev, slot->wp_pin,
-				      "mmc_wp")) {
-			dev_dbg(&mmc->class_dev, "no WP pin available\n");
-			slot->wp_pin = -EBUSY;
-		}
-	}
+	if (!slot->wp_pin)
+		dev_dbg(&mmc->class_dev, "no WP pin available\n");
 
 	host->slot[id] = slot;
 	mmc_regulator_get_supply(mmc);
@@ -2308,18 +2307,18 @@ static int atmci_init_slot(struct atmel_mci *host,
 		return ret;
 	}
 
-	if (gpio_is_valid(slot->detect_pin)) {
+	if (slot->detect_pin) {
 		timer_setup(&slot->detect_timer, atmci_detect_change, 0);
 
-		ret = request_irq(gpio_to_irq(slot->detect_pin),
-				atmci_detect_interrupt,
-				IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
-				"mmc-detect", slot);
+		ret = request_irq(gpiod_to_irq(slot->detect_pin),
+				  atmci_detect_interrupt,
+				  IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+				  "mmc-detect", slot);
 		if (ret) {
 			dev_dbg(&mmc->class_dev,
 				"could not request IRQ %d for detect pin\n",
-				gpio_to_irq(slot->detect_pin));
-			slot->detect_pin = -EBUSY;
+				gpiod_to_irq(slot->detect_pin));
+			slot->detect_pin = NULL;
 		}
 	}
 
@@ -2338,10 +2337,8 @@ static void atmci_cleanup_slot(struct atmel_mci_slot *slot,
 
 	mmc_remove_host(slot->mmc);
 
-	if (gpio_is_valid(slot->detect_pin)) {
-		int pin = slot->detect_pin;
-
-		free_irq(gpio_to_irq(pin), slot);
+	if (slot->detect_pin) {
+		free_irq(gpiod_to_irq(slot->detect_pin), slot);
 		del_timer_sync(&slot->detect_timer);
 	}
 
diff --git a/include/linux/atmel-mci.h b/include/linux/atmel-mci.h
index 1491af38cc6e..017e7d8f6126 100644
--- a/include/linux/atmel-mci.h
+++ b/include/linux/atmel-mci.h
@@ -26,8 +26,8 @@
  */
 struct mci_slot_pdata {
 	unsigned int		bus_width;
-	int			detect_pin;
-	int			wp_pin;
+	struct gpio_desc        *detect_pin;
+	struct gpio_desc	*wp_pin;
 	bool			detect_is_active_high;
 	bool			non_removable;
 };
-- 
2.25.1

[PATCH v5 2/3] mmc: atmel-mci: move atmel MCI header file

[Balamanikandan Gunasundar]

Move the contents of linux/atmel-mci.h into
drivers/mmc/host/atmel-mci.c as it is only used in one file

Signed-off-by: Balamanikandan Gunasundar <balamanikandan.gunasundar@microchip.com>
Reviewed-by: Ludovic Desroches <ludovic.desroches@microchip.com>
---
 drivers/mmc/host/atmel-mci.c | 39 +++++++++++++++++++++++++++++-
 include/linux/atmel-mci.h    | 46 ------------------------------------
 2 files changed, 38 insertions(+), 47 deletions(-)
 delete mode 100644 include/linux/atmel-mci.h

diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index 892d29fed9ec..6f815818dd22 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -29,7 +29,6 @@
 #include <linux/mmc/host.h>
 #include <linux/mmc/sdio.h>
 
-#include <linux/atmel-mci.h>
 #include <linux/atmel_pdc.h>
 #include <linux/pm.h>
 #include <linux/pm_runtime.h>
@@ -39,6 +38,8 @@
 #include <asm/io.h>
 #include <asm/unaligned.h>
 
+#define ATMCI_MAX_NR_SLOTS	2
+
 /*
  * Superset of MCI IP registers integrated in Atmel AT91 Processor
  * Registers and bitfields marked with [2] are only available in MCI2
@@ -200,6 +201,42 @@ enum atmci_pdc_buf {
 	PDC_SECOND_BUF,
 };
 
+/**
+ * struct mci_slot_pdata - board-specific per-slot configuration
+ * @bus_width: Number of data lines wired up the slot
+ * @detect_pin: GPIO pin wired to the card detect switch
+ * @wp_pin: GPIO pin wired to the write protect sensor
+ * @detect_is_active_high: The state of the detect pin when it is active
+ * @non_removable: The slot is not removable, only detect once
+ *
+ * If a given slot is not present on the board, @bus_width should be
+ * set to 0. The other fields are ignored in this case.
+ *
+ * Any pins that aren't available should be set to a negative value.
+ *
+ * Note that support for multiple slots is experimental -- some cards
+ * might get upset if we don't get the clock management exactly right.
+ * But in most cases, it should work just fine.
+ */
+struct mci_slot_pdata {
+	unsigned int		bus_width;
+	struct gpio_desc        *detect_pin;
+	struct gpio_desc	*wp_pin;
+	bool			detect_is_active_high;
+	bool			non_removable;
+};
+
+/**
+ * struct mci_platform_data - board-specific MMC/SDcard configuration
+ * @dma_slave: DMA slave interface to use in data transfers.
+ * @slot: Per-slot configuration data.
+ */
+struct mci_platform_data {
+	void			*dma_slave;
+	dma_filter_fn		dma_filter;
+	struct mci_slot_pdata	slot[ATMCI_MAX_NR_SLOTS];
+};
+
 struct atmel_mci_caps {
 	bool    has_dma_conf_reg;
 	bool    has_pdc;
diff --git a/include/linux/atmel-mci.h b/include/linux/atmel-mci.h
deleted file mode 100644
index 017e7d8f6126..000000000000
--- a/include/linux/atmel-mci.h
+++ /dev/null
@@ -1,46 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __LINUX_ATMEL_MCI_H
-#define __LINUX_ATMEL_MCI_H
-
-#include <linux/types.h>
-#include <linux/dmaengine.h>
-
-#define ATMCI_MAX_NR_SLOTS	2
-
-/**
- * struct mci_slot_pdata - board-specific per-slot configuration
- * @bus_width: Number of data lines wired up the slot
- * @detect_pin: GPIO pin wired to the card detect switch
- * @wp_pin: GPIO pin wired to the write protect sensor
- * @detect_is_active_high: The state of the detect pin when it is active
- * @non_removable: The slot is not removable, only detect once
- *
- * If a given slot is not present on the board, @bus_width should be
- * set to 0. The other fields are ignored in this case.
- *
- * Any pins that aren't available should be set to a negative value.
- *
- * Note that support for multiple slots is experimental -- some cards
- * might get upset if we don't get the clock management exactly right.
- * But in most cases, it should work just fine.
- */
-struct mci_slot_pdata {
-	unsigned int		bus_width;
-	struct gpio_desc        *detect_pin;
-	struct gpio_desc	*wp_pin;
-	bool			detect_is_active_high;
-	bool			non_removable;
-};
-
-/**
- * struct mci_platform_data - board-specific MMC/SDcard configuration
- * @dma_slave: DMA slave interface to use in data transfers.
- * @slot: Per-slot configuration data.
- */
-struct mci_platform_data {
-	void			*dma_slave;
-	dma_filter_fn		dma_filter;
-	struct mci_slot_pdata	slot[ATMCI_MAX_NR_SLOTS];
-};
-
-#endif /* __LINUX_ATMEL_MCI_H */
-- 
2.25.1

[PATCH v5 3/3] mmc: atmel-mci: Move card detect gpio polarity quirk to gpiolib

[Balamanikandan Gunasundar]

The polarity of the card detection gpio is handled by the "cd-inverted"
property in the device tree. Move this inversion logic to gpiolib to avoid
reading the gpio raw value.

Signed-off-by: Balamanikandan Gunasundar <balamanikandan.gunasundar@microchip.com>
---
 drivers/gpio/gpiolib-of.c    |  7 +++++++
 drivers/mmc/host/atmel-mci.c | 33 +++++++++++++++------------------
 2 files changed, 22 insertions(+), 18 deletions(-)

diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index 1436cdb5fa26..87d652c62339 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -257,6 +257,13 @@ static void of_gpio_set_polarity_by_property(const struct device_node *np,
 	unsigned int i;
 	bool active_high;
 
+#if IS_ENABLED(CONFIG_MMC_ATMELMCI)
+	if (of_device_is_compatible(np->parent, "atmel,hsmci") &&
+	    !strcmp(propname, "cd-gpios")) {
+		active_high = of_property_read_bool(np, "cd-inverted");
+		of_gpio_quirk_polarity(np, active_high, flags);
+	}
+#endif
 	for (i = 0; i < ARRAY_SIZE(gpios); i++) {
 		if (of_device_is_compatible(np, gpios[i].compatible) &&
 		    !strcmp(propname, gpios[i].gpio_propname)) {
diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index 6f815818dd22..535783c43105 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -206,7 +206,6 @@ enum atmci_pdc_buf {
  * @bus_width: Number of data lines wired up the slot
  * @detect_pin: GPIO pin wired to the card detect switch
  * @wp_pin: GPIO pin wired to the write protect sensor
- * @detect_is_active_high: The state of the detect pin when it is active
  * @non_removable: The slot is not removable, only detect once
  *
  * If a given slot is not present on the board, @bus_width should be
@@ -222,7 +221,6 @@ struct mci_slot_pdata {
 	unsigned int		bus_width;
 	struct gpio_desc        *detect_pin;
 	struct gpio_desc	*wp_pin;
-	bool			detect_is_active_high;
 	bool			non_removable;
 };
 
@@ -405,7 +403,6 @@ struct atmel_mci {
  *	available.
  * @wp_pin: GPIO pin used for card write protect sending, or negative
  *	if not available.
- * @detect_is_active_high: The state of the detect pin when it is active.
  * @detect_timer: Timer used for debouncing @detect_pin interrupts.
  */
 struct atmel_mci_slot {
@@ -426,7 +423,6 @@ struct atmel_mci_slot {
 
 	struct gpio_desc        *detect_pin;
 	struct gpio_desc	*wp_pin;
-	bool			detect_is_active_high;
 
 	struct timer_list	detect_timer;
 };
@@ -644,6 +640,7 @@ atmci_of_init(struct platform_device *pdev)
 	struct device_node *cnp;
 	struct mci_platform_data *pdata;
 	u32 slot_id;
+	int err;
 
 	if (!np) {
 		dev_err(&pdev->dev, "device node not found\n");
@@ -675,11 +672,12 @@ atmci_of_init(struct platform_device *pdev)
 		pdata->slot[slot_id].detect_pin =
 			devm_fwnode_gpiod_get(&pdev->dev, of_fwnode_handle(cnp),
 					      "cd", GPIOD_IN, "cd-gpios");
-		if (IS_ERR(pdata->slot[slot_id].detect_pin))
+		err = PTR_ERR_OR_ZERO(pdata->slot[slot_id].detect_pin);
+		if (err) {
+			if (err != -ENOENT)
+				return ERR_PTR(err);
 			pdata->slot[slot_id].detect_pin = NULL;
-
-		pdata->slot[slot_id].detect_is_active_high =
-			of_property_read_bool(cnp, "cd-inverted");
+		}
 
 		pdata->slot[slot_id].non_removable =
 			of_property_read_bool(cnp, "non-removable");
@@ -687,8 +685,12 @@ atmci_of_init(struct platform_device *pdev)
 		pdata->slot[slot_id].wp_pin =
 			devm_fwnode_gpiod_get(&pdev->dev, of_fwnode_handle(cnp),
 					      "wp", GPIOD_IN, "wp-gpios");
-		if (IS_ERR(pdata->slot[slot_id].wp_pin))
+		err = PTR_ERR_OR_ZERO(pdata->slot[slot_id].wp_pin);
+		if (err) {
+			if (err != -ENOENT)
+				return ERR_PTR(err);
 			pdata->slot[slot_id].wp_pin = NULL;
+		}
 	}
 
 	return pdata;
@@ -1566,8 +1568,7 @@ static int atmci_get_cd(struct mmc_host *mmc)
 	struct atmel_mci_slot	*slot = mmc_priv(mmc);
 
 	if (slot->detect_pin) {
-		present = !(gpiod_get_raw_value(slot->detect_pin) ^
-			    slot->detect_is_active_high);
+		present = gpiod_get_value_cansleep(slot->detect_pin);
 		dev_dbg(&mmc->class_dev, "card is %spresent\n",
 				present ? "" : "not ");
 	}
@@ -1680,8 +1681,7 @@ static void atmci_detect_change(struct timer_list *t)
 		return;
 
 	enable_irq(gpiod_to_irq(slot->detect_pin));
-	present = !(gpiod_get_raw_value(slot->detect_pin) ^
-		    slot->detect_is_active_high);
+	present = gpiod_get_value_cansleep(slot->detect_pin);
 	present_old = test_bit(ATMCI_CARD_PRESENT, &slot->flags);
 
 	dev_vdbg(&slot->mmc->class_dev, "detect change: %d (was %d)\n",
@@ -2272,7 +2272,6 @@ static int atmci_init_slot(struct atmel_mci *host,
 	slot->host = host;
 	slot->detect_pin = slot_data->detect_pin;
 	slot->wp_pin = slot_data->wp_pin;
-	slot->detect_is_active_high = slot_data->detect_is_active_high;
 	slot->sdc_reg = sdc_reg;
 	slot->sdio_irq = sdio_irq;
 
@@ -2280,7 +2279,7 @@ static int atmci_init_slot(struct atmel_mci *host,
 	        "slot[%u]: bus_width=%u, detect_pin=%d, "
 		"detect_is_active_high=%s, wp_pin=%d\n",
 		id, slot_data->bus_width, desc_to_gpio(slot_data->detect_pin),
-		slot_data->detect_is_active_high ? "true" : "false",
+		!gpiod_is_active_low(slot_data->detect_pin) ? "true" : "false",
 		desc_to_gpio(slot_data->wp_pin));
 
 	mmc->ops = &atmci_ops;
@@ -2318,10 +2317,8 @@ static int atmci_init_slot(struct atmel_mci *host,
 	/* Assume card is present initially */
 	set_bit(ATMCI_CARD_PRESENT, &slot->flags);
 	if (slot->detect_pin) {
-		if (gpiod_get_raw_value(slot->detect_pin) ^
-		    slot->detect_is_active_high) {
+		if (!gpiod_get_value_cansleep(slot->detect_pin))
 			clear_bit(ATMCI_CARD_PRESENT, &slot->flags);
-		}
 	} else {
 		dev_dbg(&mmc->class_dev, "no detect pin available\n");
 	}
-- 
2.25.1

Re: [PATCH v5 3/3] mmc: atmel-mci: Move card detect gpio polarity quirk to gpiolib

[Linus Walleij]

Hi Balamanikandan,

thanks for your patch!

On Wed, Aug 23, 2023 at 12:40 PM Balamanikandan Gunasundar
<balamanikandan.gunasundar@microchip.com> wrote:

> The polarity of the card detection gpio is handled by the "cd-inverted"
> property in the device tree. Move this inversion logic to gpiolib to avoid
> reading the gpio raw value.
>
> Signed-off-by: Balamanikandan Gunasundar <balamanikandan.gunasundar@microchip.com>
(...)
>  drivers/gpio/gpiolib-of.c    |  7 +++++++

Patching here is the right approach!

> +#if IS_ENABLED(CONFIG_MMC_ATMELMCI)
> +       if (of_device_is_compatible(np->parent, "atmel,hsmci") &&
> +           !strcmp(propname, "cd-gpios")) {
> +               active_high = of_property_read_bool(np, "cd-inverted");
> +               of_gpio_quirk_polarity(np, active_high, flags);
> +       }
> +#endif
>         for (i = 0; i < ARRAY_SIZE(gpios); i++) {
>                 if (of_device_is_compatible(np, gpios[i].compatible) &&
>                     !strcmp(propname, gpios[i].gpio_propname)) {

This duplicates the code right below. Can't you just add an entry to the
existing gpios[] array?

I would imagine:

    static const struct {
        const char *compatible;
        const char *gpio_propname;
        const char *polarity_propname;
    } gpios[] = {
#if IS_ENABLED(CONFIG_MMC_ATMELMCI)
        { "atmel,hsmci", "cd-gpios", "cd-inverted" },
#endif
(...)


Yours,
Linus Walleij

Re: [PATCH v5 3/3] mmc: atmel-mci: Move card detect gpio polarity quirk to gpiolib

[Balamanikandan.Gunasundar]

Hi Linus,

Thanks for reviewing the patch.

On 23/08/23 6:11 pm, Linus Walleij wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> Hi Balamanikandan,
> 
> thanks for your patch!
> 
> On Wed, Aug 23, 2023 at 12:40 PM Balamanikandan Gunasundar
> <balamanikandan.gunasundar@microchip.com> wrote:
> 
>> The polarity of the card detection gpio is handled by the "cd-inverted"
>> property in the device tree. Move this inversion logic to gpiolib to avoid
>> reading the gpio raw value.
>>
>> Signed-off-by: Balamanikandan Gunasundar <balamanikandan.gunasundar@microchip.com>
> (...)
>>   drivers/gpio/gpiolib-of.c    |  7 +++++++
> 
> Patching here is the right approach!
> 
>> +#if IS_ENABLED(CONFIG_MMC_ATMELMCI)
>> +       if (of_device_is_compatible(np->parent, "atmel,hsmci") &&

The only difference above is "np->parent" while the existing code uses 
"np". This is because the compatible string is defined in the parent 
node here while the others have it in the same node.

mmc0: mmc@f0000000 {
	compatible = "atmel,hsmci";
	...
	
	slot@0 {
		cd-gpios = <&pioE 0 GPIO_ACTIVE_LOW>;
		cd-inverted;
	}
}

>> +           !strcmp(propname, "cd-gpios")) {
>> +               active_high = of_property_read_bool(np, "cd-inverted");
>> +               of_gpio_quirk_polarity(np, active_high, flags);
>> +       }
>> +#endif
>>          for (i = 0; i < ARRAY_SIZE(gpios); i++) {
>>                  if (of_device_is_compatible(np, gpios[i].compatible) &&
>>                      !strcmp(propname, gpios[i].gpio_propname)) {
> 
> This duplicates the code right below. Can't you just add an entry to the
> existing gpios[] array?

Yes! I attempted to do so. But as explained above in this particular 
case, of_device_is_compatible(np->parent, ..) should be called. Adding a 
condition check here looked clumsy.

> 
> I would imagine:
> 
>      static const struct {
>          const char *compatible;
>          const char *gpio_propname;
>          const char *polarity_propname;
>      } gpios[] = {
> #if IS_ENABLED(CONFIG_MMC_ATMELMCI)
>          { "atmel,hsmci", "cd-gpios", "cd-inverted" },
> #endif
> (...)
> 

I think with the above entry I can also add a check like ...

if (np->parent) {
	if (of_device_is_compatible(np->parent, "atmel,hsmci") &&
		!strcmp(propname, gpios[i].gpio_propname))
		active_high = of_property_read_bool();
}

Please let me know your thoughts.

Thanks,
Balamanikandan

> 
> Yours,
> Linus Walleij

Re: [PATCH v5 3/3] mmc: atmel-mci: Move card detect gpio polarity quirk to gpiolib

[Linus Walleij]

On Thu, Aug 24, 2023 at 8:39 AM <Balamanikandan.Gunasundar@microchip.com> wrote:

> >> +#if IS_ENABLED(CONFIG_MMC_ATMELMCI)
> >> +       if (of_device_is_compatible(np->parent, "atmel,hsmci") &&
>
> The only difference above is "np->parent" while the existing code uses
> "np". This is because the compatible string is defined in the parent
> node here while the others have it in the same node.

Aha. What about this right before the for-loop
then:

/* The Atmel MSMCI has the property in a child node of the device */
if (IS_ENABLED(CONFIG_MMC_ATMELMCI) &&
of_device_is_compatible(np->parent, "atmel,hsmci"))
  np = parent->np;

Yours,
Linus Walleij

Re: [PATCH v5 3/3] mmc: atmel-mci: Move card detect gpio polarity quirk to gpiolib

[Balamanikandan.Gunasundar]

On 24/08/23 2:03 pm, Linus Walleij wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> On Thu, Aug 24, 2023 at 8:39 AM <Balamanikandan.Gunasundar@microchip.com> wrote:
> 
>>>> +#if IS_ENABLED(CONFIG_MMC_ATMELMCI)
>>>> +       if (of_device_is_compatible(np->parent, "atmel,hsmci") &&
>>
>> The only difference above is "np->parent" while the existing code uses
>> "np". This is because the compatible string is defined in the parent
>> node here while the others have it in the same node.
> 
> Aha. What about this right before the for-loop
> then:
> 
> /* The Atmel MSMCI has the property in a child node of the device */
> if (IS_ENABLED(CONFIG_MMC_ATMELMCI) &&
> of_device_is_compatible(np->parent, "atmel,hsmci"))
>    np = parent->np;
> 

This looks good! I will send a v6.

Thanks,
Balamanikandan

> Yours,
> Linus Walleij