On 18.04.2012 15:46, Wolfram Sang wrote: > >>>> Optional properties: >>>> + - gpios: The order of the gpios should be the following: <SDA, SCL>. >>>> + The gpio specifier depends on the gpio controller. Required in all cases >>>> + except when "samsung,i2c-no-gpio" is also specified. >>>> + - samsung,i2c-no-gpio: input/output lines of the controller are >>>> + permanently wired to the respective client, there are no gpio >>>> + lines that need to be configured to enable this controller >>> >>> Can't we just skip this property... >> >> All standard s3c-24x0 i2c controllers require gpio lines for proper operation, >> so lack of the gpios property should be considered as an error. However there >> is a special case of internal, embedded i2c controller which has no such gpio >> lines at all. >> >>>> - samsung,i2c-slave-addr: Slave address in multi-master enviroment. If not >>>> specified, default value is 0. >>>> - samsung,i2c-max-bus-freq: Desired frequency in Hz of the bus. If not >>>> specified, the default value in Hz is 100000. >>>> + - samsung,i2c-quirk-hdmiphy: Quirk for HDMI PHY block found on >>>> + Exynos4 platform - reduce timeout and reset controller after each >>>> + transfer >>> >>> ... and this one, if we declare a new compatible-entry for exynos4? >> >> It is not strictly related to Exynos4 SoCs. Exynos4 SoC has 8 standard s3c2440 style >> i2c controllers and one additional, internal controller for HDMIPHY, which needs >> some workarounds in the driver. Maybe the quirk should be named 'broken timeout >> detection' > > I was wondering since you do what I suggested for platform devices already: > > + .name = "s3c2440-hdmiphy-i2c", > + .driver_data = QUIRK_S3C2440 | QUIRK_HDMIPHY | QUIRK_NO_GPIO, Here I've done it this way for compatibility with legacy driver and board(s). Device tree is new interface, and I thought that it would be better to describe things explicitly and separately from device type. Right now these properties are used only on S3C2440, but I don't consider it highly unlikely to see these on S3C**** in future. Tomasz had similar doubts when I've posted patch that checked these quirks only for S3C2440: http://permalink.gmane.org/gmane.linux.drivers.i2c/10305 Thus, I've chosen properties and not separate type. It's easy to introduce compat string (see below), but given above I'm afraid that we might end up adding -hdmiphy- variant for every new version of i2c controller. E.g. diff --git a/Documentation/devicetree/bindings/i2c/samsung-i2c.txt b/Documentation/devicetree/bindings/i2c/samsung-i2c.txt index c6670f9..b1d106e 100644 --- a/Documentation/devicetree/bindings/i2c/samsung-i2c.txt +++ b/Documentation/devicetree/bindings/i2c/samsung-i2c.txt @@ -6,6 +6,8 @@ Required properties: - compatible: value should be either of the following. (a) "samsung, s3c2410-i2c", for i2c compatible with s3c2410 i2c. (b) "samsung, s3c2440-i2c", for i2c compatible with s3c2440 i2c. + (c) "samsung, s3c2440-hdmiphy-i2c", for s3c2440-like i2c used + inside HDMIPHY block found on several samsung SoCs - reg: physical base address of the controller and length of memory mapped region. - interrupts: interrupt number to the cpu. @@ -13,18 +15,13 @@ Required properties: Optional properties: - gpios: The order of the gpios should be the following: <SDA, SCL>. - The gpio specifier depends on the gpio controller. Required in all cases - except when "samsung,i2c-no-gpio" is also specified. - - samsung,i2c-no-gpio: input/output lines of the controller are - permanently wired to the respective client, there are no gpio - lines that need to be configured to enable this controller + The gpio specifier depends on the gpio controller. Required in all + cases except for "samsung,i2c-hdmiphy-i2c" whose input/output + lines are permanently wired to the respective client - samsung,i2c-slave-addr: Slave address in multi-master enviroment. If not specified, default value is 0. - samsung,i2c-max-bus-freq: Desired frequency in Hz of the bus. If not specified, the default value in Hz is 100000. - - samsung,i2c-quirk-hdmiphy: Quirk for HDMI PHY block found on - Exynos4 platform - reduce timeout and reset controller after each - transfer Example: diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c index 71438eb..bc82045 100644 --- a/drivers/i2c/busses/i2c-s3c2410.c +++ b/drivers/i2c/busses/i2c-s3c2410.c @@ -106,6 +106,8 @@ MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids); static const struct of_device_id s3c24xx_i2c_match[] = { { .compatible = "samsung,s3c2410-i2c", .data = (void *)0 }, { .compatible = "samsung,s3c2440-i2c", .data = (void *)QUIRK_S3C2440 }, + { .compatible = "samsung,s3c2440-hdmiphy-i2c", + .data = (void *)(QUIRK_S3C2440 | QUIRK_HDMIPHY | QUIRK_NO_GPIO) }, {}, }; MODULE_DEVICE_TABLE(of, s3c24xx_i2c_match); @@ -902,12 +904,6 @@ s3c24xx_i2c_parse_dt(struct device_node *np, struct s3c24xx_i2c *i2c) pdata->bus_num = -1; /* i2c bus number is dynamically assigned */ - if (of_get_property(np, "samsung,i2c-quirk-hdmiphy", NULL)) - i2c->quirks |= QUIRK_HDMIPHY; - - if (of_get_property(np, "samsung,i2c-no-gpio", NULL)) - i2c->quirks |= QUIRK_NO_GPIO; - of_property_read_u32(np, "samsung,i2c-sda-delay", &pdata->sda_delay); of_property_read_u32(np, "samsung,i2c-slave-addr", &pdata->slave_addr); of_property_read_u32(np, "samsung,i2c-max-bus-freq", Regards, -- Karol Lewandowski | Samsung Poland R&D Center | Linux/Platform -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
