Commit abc925f7 authored by Alexandre Belloni's avatar Alexandre Belloni
Browse files

rtc: ds1307: use generic nvmem 



Instead of adding a binary sysfs attribute from the driver (which suffers
from a race condition as the attribute appears after the device), use the
core to register an nvmem device.

Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@free-electrons.com>
parent 69b119a6

drivers/rtc/rtc-ds1307.c

+22 −66
Original line number Diff line number Diff line
@@ -118,7 +118,7 @@ struct ds1307 { 
	u8			offset; /* register's offset */

	u8			regs[11];

	u16			nvram_offset;

	struct bin_attribute	*nvram;

	struct nvmem_config	nvmem_cfg;

	enum ds_type		type;

	unsigned long		flags;

#define HAS_NVRAM	0		/* bit 0 == sysfs file active */
@@ -895,42 +895,23 @@ static const struct rtc_class_ops mcp794xx_rtc_ops = { 


/*----------------------------------------------------------------------*/



static ssize_t

ds1307_nvram_read(struct file *filp, struct kobject *kobj,

		struct bin_attribute *attr,

		char *buf, loff_t off, size_t count)

static int ds1307_nvram_read(void *priv, unsigned int offset, void *val,

			     size_t bytes)

{

	struct ds1307		*ds1307;

	int			result;



	ds1307 = dev_get_drvdata(kobj_to_dev(kobj));

	struct ds1307 *ds1307 = priv;



	result = regmap_bulk_read(ds1307->regmap, ds1307->nvram_offset + off,

				  buf, count);

	if (result)

		dev_err(ds1307->dev, "%s error %d\n", "nvram read", result);

	return result;

	return regmap_bulk_read(ds1307->regmap, ds1307->nvram_offset + offset,

				val, bytes);

}



static ssize_t

ds1307_nvram_write(struct file *filp, struct kobject *kobj,

		struct bin_attribute *attr,

		char *buf, loff_t off, size_t count)

static int ds1307_nvram_write(void *priv, unsigned int offset, void *val,

			      size_t bytes)

{

	struct ds1307		*ds1307;

	int			result;

	struct ds1307 *ds1307 = priv;



	ds1307 = dev_get_drvdata(kobj_to_dev(kobj));



	result = regmap_bulk_write(ds1307->regmap, ds1307->nvram_offset + off,

				   buf, count);

	if (result) {

		dev_err(ds1307->dev, "%s error %d\n", "nvram write", result);

		return result;

	return regmap_bulk_write(ds1307->regmap, ds1307->nvram_offset + offset,

				 val, bytes);

}

	return count;

}





/*----------------------------------------------------------------------*/
@@ -1704,37 +1685,17 @@ read_rtc: 
	}



	if (chip->nvram_size) {



		ds1307->nvram = devm_kzalloc(ds1307->dev,

					sizeof(struct bin_attribute),

					GFP_KERNEL);

		if (!ds1307->nvram) {

			dev_err(ds1307->dev,

				"cannot allocate memory for nvram sysfs\n");

		} else {



			ds1307->nvram->attr.name = "nvram";

			ds1307->nvram->attr.mode = S_IRUGO | S_IWUSR;



			sysfs_bin_attr_init(ds1307->nvram);



			ds1307->nvram->read = ds1307_nvram_read;

			ds1307->nvram->write = ds1307_nvram_write;

			ds1307->nvram->size = chip->nvram_size;

		ds1307->nvmem_cfg.name = "ds1307_nvram";

		ds1307->nvmem_cfg.word_size = 1;

		ds1307->nvmem_cfg.stride = 1;

		ds1307->nvmem_cfg.size = chip->nvram_size;

		ds1307->nvmem_cfg.reg_read = ds1307_nvram_read;

		ds1307->nvmem_cfg.reg_write = ds1307_nvram_write;

		ds1307->nvmem_cfg.priv = ds1307;

		ds1307->nvram_offset = chip->nvram_offset;



			err = sysfs_create_bin_file(&ds1307->dev->kobj,

						    ds1307->nvram);

			if (err) {

				dev_err(ds1307->dev,

					"unable to create sysfs file: %s\n",

					ds1307->nvram->attr.name);

			} else {

				set_bit(HAS_NVRAM, &ds1307->flags);

				dev_info(ds1307->dev, "%zu bytes nvram\n",

					 ds1307->nvram->size);

			}

		}

		ds1307->rtc->nvmem_config = &ds1307->nvmem_cfg;

		ds1307->rtc->nvram_old_abi = true;

	}



	ds1307->rtc->ops = rtc_ops;
@@ -1753,11 +1714,6 @@ exit: 


static int ds1307_remove(struct i2c_client *client)

{

	struct ds1307 *ds1307 = i2c_get_clientdata(client);



	if (test_and_clear_bit(HAS_NVRAM, &ds1307->flags))

		sysfs_remove_bin_file(&ds1307->dev->kobj, ds1307->nvram);



	return 0;

}

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