On Thu, Feb 9, 2017 at 7:36 PM, Ben Gardner <gardner....@gmail.com> wrote:
> Allow the at24 driver to get configuration information from both OF and
> ACPI by using the more generic device_property functions.
> This change was inspired by the at25.c driver.
>
> I have a custom board with a ST M24C02 EEPROM attached to an I2C bus.
> With the following ACPI construct, this patch instantiates a working
> instance of the driver.
>
> Device (EEP0) {
> Name (_HID, "PRP0001")
> Name (_DSD, Package () {
> ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
> Package () {
> Package () {"compatible", Package () {"st,24c02"}},
> Package () {"pagesize", 16},
> },
> })
> Name (_CRS, ResourceTemplate () {
> I2cSerialBus (
> 0x0057, ControllerInitiated, 400000,
> AddressingMode7Bit, "\\_SB.PCI0.I2C3", 0x00,
> ResourceConsumer,,)
> })
> }
>
> Note: Matching the driver to the I2C device requires another patch.
> http://www.spinics.net/lists/linux-acpi/msg71914.html
Reviewed-by: Andy Shevchenko <andy.shevche...@gmail.com>
> Signed-off-by: Ben Gardner <gardner....@gmail.com>
> ---
> drivers/misc/eeprom/at24.c | 45 +++++++++++++++++++--------------------------
> 1 file changed, 19 insertions(+), 26 deletions(-)
>
> diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
> index 051b147..764ff5df 100644
> --- a/drivers/misc/eeprom/at24.c
> +++ b/drivers/misc/eeprom/at24.c
> @@ -19,7 +19,7 @@
> #include <linux/log2.h>
> #include <linux/bitops.h>
> #include <linux/jiffies.h>
> -#include <linux/of.h>
> +#include <linux/property.h>
> #include <linux/acpi.h>
> #include <linux/i2c.h>
> #include <linux/nvmem-provider.h>
> @@ -562,26 +562,26 @@ static int at24_write(void *priv, unsigned int off,
> void *val, size_t count)
> return 0;
> }
>
> -#ifdef CONFIG_OF
> -static void at24_get_ofdata(struct i2c_client *client,
> - struct at24_platform_data *chip)
> +static void at24_get_pdata(struct device *dev, struct at24_platform_data
> *chip)
> {
> - const __be32 *val;
> - struct device_node *node = client->dev.of_node;
> -
> - if (node) {
> - if (of_get_property(node, "read-only", NULL))
> - chip->flags |= AT24_FLAG_READONLY;
> - val = of_get_property(node, "pagesize", NULL);
> - if (val)
> - chip->page_size = be32_to_cpup(val);
> + int err;
> + u32 val;
> +
> + if (device_property_present(dev, "read-only"))
> + chip->flags |= AT24_FLAG_READONLY;
> +
> + err = device_property_read_u32(dev, "pagesize", &val);
> + if (!err) {
> + chip->page_size = val;
> + } else {
> + /*
> + * This is slow, but we can't know all eeproms, so we better
> + * play safe. Specifying custom eeprom-types via platform_data
> + * is recommended anyhow.
> + */
> + chip->page_size = 1;
> }
> }
> -#else
> -static void at24_get_ofdata(struct i2c_client *client,
> - struct at24_platform_data *chip)
> -{ }
> -#endif /* CONFIG_OF */
>
> static int at24_probe(struct i2c_client *client, const struct i2c_device_id
> *id)
> {
> @@ -613,15 +613,8 @@ static int at24_probe(struct i2c_client *client, const
> struct i2c_device_id *id)
> chip.byte_len = BIT(magic & AT24_BITMASK(AT24_SIZE_BYTELEN));
> magic >>= AT24_SIZE_BYTELEN;
> chip.flags = magic & AT24_BITMASK(AT24_SIZE_FLAGS);
> - /*
> - * This is slow, but we can't know all eeproms, so we better
> - * play safe. Specifying custom eeprom-types via platform_data
> - * is recommended anyhow.
> - */
> - chip.page_size = 1;
>
> - /* update chipdata if OF is present */
> - at24_get_ofdata(client, &chip);
> + at24_get_pdata(&client->dev, &chip);
>
> chip.setup = NULL;
> chip.context = NULL;
> --
> 2.7.4
>
--
With Best Regards,
Andy Shevchenko
