Commit 6810df46 authored by Wolfram Sang's avatar Wolfram Sang
Browse files

Merge tag 'at24-updates-for-v5.6' of... 

Merge tag 'at24-updates-for-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into i2c/for-5.6

at24 updates for linux v5.6

- minor maintenance: update the license tag, sort headers
- move support for the write-protect pin into nvmem core
- add a reference to the new wp-gpios property in nvmem to at25 bindings
- add support for regulator and pm_runtime control
parents 878508ae cd5676db

Documentation/devicetree/bindings/eeprom/at24.yaml

+5 −4
Original line number Diff line number Diff line
@@ -145,10 +145,7 @@ properties: 
      over reads to the next slave address. Please consult the manual of

      your device.



  wp-gpios:

    description:

      GPIO to which the write-protect pin of the chip is connected.

    maxItems: 1

  wp-gpios: true



  address-width:

    allOf:
@@ -167,6 +164,10 @@ properties: 
    minimum: 1

    maximum: 8



  vcc-supply:

    description:

      phandle of the regulator that provides the supply voltage.



required:

  - compatible

  - reg

Documentation/devicetree/bindings/eeprom/at25.txt

+2 −0
Original line number Diff line number Diff line
@@ -20,6 +20,7 @@ Optional properties: 
- spi-cpha : SPI shifted clock phase, as per spi-bus bindings.

- spi-cpol : SPI inverse clock polarity, as per spi-bus bindings.

- read-only : this parameter-less property disables writes to the eeprom

- wp-gpios : GPIO to which the write-protect pin of the chip is connected



Obsolete legacy properties can be used in place of "size", "pagesize",

"address-width", and "read-only":
@@ -36,6 +37,7 @@ Example: 
		spi-max-frequency = <5000000>;

		spi-cpha;

		spi-cpol;

		wp-gpios = <&gpio1 3 0>;



		pagesize = <64>;

		size = <32768>;

Documentation/devicetree/bindings/nvmem/nvmem.yaml

+11 −0
Original line number Diff line number Diff line
@@ -34,6 +34,14 @@ properties: 
    description:

      Mark the provider as read only.



  wp-gpios:

    description:

      GPIO to which the write-protect pin of the chip is connected.

      The write-protect GPIO is asserted, when it's driven high

      (logical '1') to block the write operation. It's deasserted,

      when it's driven low (logical '0') to allow writing.

    maxItems: 1



patternProperties:

  "^.*@[0-9a-f]+$":

    type: object
@@ -63,9 +71,12 @@ patternProperties: 


examples:

  - |

      #include <dt-bindings/gpio/gpio.h>



      qfprom: eeprom@700000 {

          #address-cells = <1>;

          #size-cells = <1>;

          wp-gpios = <&gpio1 3 GPIO_ACTIVE_HIGH>;



          /* ... */

drivers/misc/eeprom/at24.c

+51 −21
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0+

// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * at24.c - handle most I2C EEPROMs

 *
@@ -6,23 +6,23 @@ 
 * Copyright (C) 2008 Wolfram Sang, Pengutronix

 */



#include <linux/kernel.h>

#include <linux/acpi.h>

#include <linux/bitops.h>

#include <linux/delay.h>

#include <linux/i2c.h>

#include <linux/init.h>

#include <linux/jiffies.h>

#include <linux/kernel.h>

#include <linux/mod_devicetable.h>

#include <linux/module.h>

#include <linux/of_device.h>

#include <linux/slab.h>

#include <linux/delay.h>

#include <linux/mutex.h>

#include <linux/mod_devicetable.h>

#include <linux/bitops.h>

#include <linux/jiffies.h>

#include <linux/property.h>

#include <linux/acpi.h>

#include <linux/i2c.h>

#include <linux/nvmem-provider.h>

#include <linux/regmap.h>

#include <linux/of_device.h>

#include <linux/pm_runtime.h>

#include <linux/gpio/consumer.h>

#include <linux/property.h>

#include <linux/regmap.h>

#include <linux/regulator/consumer.h>

#include <linux/slab.h>



/* Address pointer is 16 bit. */

#define AT24_FLAG_ADDR16	BIT(7)
@@ -88,8 +88,7 @@ struct at24_data { 
	u8 flags;



	struct nvmem_device *nvmem;



	struct gpio_desc *wp_gpio;

	struct regulator *vcc_reg;



	/*

	 * Some chips tie up multiple I2C addresses; dummy devices reserve
@@ -457,12 +456,10 @@ static int at24_write(void *priv, unsigned int off, void *val, size_t count) 
	 * from this host, but not from other I2C masters.

	 */

	mutex_lock(&at24->lock);

	gpiod_set_value_cansleep(at24->wp_gpio, 0);



	while (count) {

		ret = at24_regmap_write(at24, buf, off, count);

		if (ret < 0) {

			gpiod_set_value_cansleep(at24->wp_gpio, 1);

			mutex_unlock(&at24->lock);

			pm_runtime_put(dev);

			return ret;
@@ -472,7 +469,6 @@ static int at24_write(void *priv, unsigned int off, void *val, size_t count) 
		count -= ret;

	}



	gpiod_set_value_cansleep(at24->wp_gpio, 1);

	mutex_unlock(&at24->lock);



	pm_runtime_put(dev);
@@ -662,9 +658,9 @@ static int at24_probe(struct i2c_client *client) 
	at24->client[0].client = client;

	at24->client[0].regmap = regmap;



	at24->wp_gpio = devm_gpiod_get_optional(dev, "wp", GPIOD_OUT_HIGH);

	if (IS_ERR(at24->wp_gpio))

		return PTR_ERR(at24->wp_gpio);

	at24->vcc_reg = devm_regulator_get(dev, "vcc");

	if (IS_ERR(at24->vcc_reg))

		return PTR_ERR(at24->vcc_reg);



	writable = !(flags & AT24_FLAG_READONLY);

	if (writable) {
@@ -701,6 +697,12 @@ static int at24_probe(struct i2c_client *client) 


	i2c_set_clientdata(client, at24);



	err = regulator_enable(at24->vcc_reg);

	if (err) {

		dev_err(dev, "Failed to enable vcc regulator\n");

		return err;

	}



	/* enable runtime pm */

	pm_runtime_set_active(dev);

	pm_runtime_enable(dev);
@@ -713,6 +715,7 @@ static int at24_probe(struct i2c_client *client) 
	pm_runtime_idle(dev);

	if (err) {

		pm_runtime_disable(dev);

		regulator_disable(at24->vcc_reg);

		return -ENODEV;

	}
@@ -728,15 +731,42 @@ static int at24_probe(struct i2c_client *client) 


static int at24_remove(struct i2c_client *client)

{

	struct at24_data *at24 = i2c_get_clientdata(client);



	pm_runtime_disable(&client->dev);

	if (!pm_runtime_status_suspended(&client->dev))

		regulator_disable(at24->vcc_reg);

	pm_runtime_set_suspended(&client->dev);



	return 0;

}



static int __maybe_unused at24_suspend(struct device *dev)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct at24_data *at24 = i2c_get_clientdata(client);



	return regulator_disable(at24->vcc_reg);

}



static int __maybe_unused at24_resume(struct device *dev)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct at24_data *at24 = i2c_get_clientdata(client);



	return regulator_enable(at24->vcc_reg);

}



static const struct dev_pm_ops at24_pm_ops = {

	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,

				pm_runtime_force_resume)

	SET_RUNTIME_PM_OPS(at24_suspend, at24_resume, NULL)

};



static struct i2c_driver at24_driver = {

	.driver = {

		.name = "at24",

		.pm = &at24_pm_ops,

		.of_match_table = at24_of_match,

		.acpi_match_table = ACPI_PTR(at24_acpi_ids),

	},

drivers/nvmem/core.c

+17 −2
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 
#include <linux/module.h>

#include <linux/nvmem-consumer.h>

#include <linux/nvmem-provider.h>

#include <linux/gpio/consumer.h>

#include <linux/of.h>

#include <linux/slab.h>

#include "nvmem.h"
@@ -54,8 +55,14 @@ static int nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset, 
static int nvmem_reg_write(struct nvmem_device *nvmem, unsigned int offset,

			   void *val, size_t bytes)

{

	if (nvmem->reg_write)

		return nvmem->reg_write(nvmem->priv, offset, val, bytes);

	int ret;



	if (nvmem->reg_write) {

		gpiod_set_value_cansleep(nvmem->wp_gpio, 0);

		ret = nvmem->reg_write(nvmem->priv, offset, val, bytes);

		gpiod_set_value_cansleep(nvmem->wp_gpio, 1);

		return ret;

	}



	return -EINVAL;

}
@@ -338,6 +345,14 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config) 
		kfree(nvmem);

		return ERR_PTR(rval);

	}

	if (config->wp_gpio)

		nvmem->wp_gpio = config->wp_gpio;

	else

		nvmem->wp_gpio = gpiod_get_optional(config->dev, "wp",

						    GPIOD_OUT_HIGH);

	if (IS_ERR(nvmem->wp_gpio))

		return ERR_CAST(nvmem->wp_gpio);





	kref_init(&nvmem->refcnt);

	INIT_LIST_HEAD(&nvmem->cells);

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