From 7954763bb95fd484a76d1151b40956fe331d23b9 Mon Sep 17 00:00:00 2001 From: Jarkko Nikula Date: Mon, 23 Mar 2009 18:07:48 -0700 Subject: [PATCH] ARM: OMAP: Add method to register additional I2C busses on the command line, v2 This patch extends command line option "i2c_bus=bus_id,clkrate" so that it allow to register additional I2C busses that are not registered with omap_register_i2c_bus from board initialization code. Purpose of this is to register additional board busses which are routed to external connectors only without any on board I2C devices. Cc: linux-i2c@vger.kernel.org Signed-off-by: Jarkko Nikula Signed-off-by: Tony Lindgren --- Documentation/kernel-parameters.txt | 2 + arch/arm/plat-omap/i2c.c | 73 ++++++++++++++++++++--------- 2 files changed, 54 insertions(+), 21 deletions(-) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index d775076d1563..ef9827f7c84e 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -831,6 +831,8 @@ and is between 256 and 4096 characters. It is defined in the file terminal devices. Valid values: 0..8 i2c_bus= [HW] Override the default board specific I2C bus speed + or register an additional I2C bus that is not + registered from board initialization code. Format: , diff --git a/arch/arm/plat-omap/i2c.c b/arch/arm/plat-omap/i2c.c index aa70e435fa79..a303071d5e36 100644 --- a/arch/arm/plat-omap/i2c.c +++ b/arch/arm/plat-omap/i2c.c @@ -98,6 +98,8 @@ static const int omap34xx_pins[][2] = { static const int omap34xx_pins[][2] = {}; #endif +#define OMAP_I2C_CMDLINE_SETUP (BIT(31)) + static void __init omap_i2c_mux_pins(int bus) { int scl, sda; @@ -133,6 +135,31 @@ static int __init omap_i2c_nr_ports(void) return ports; } +static int __init omap_i2c_add_bus(int bus_id) +{ + struct platform_device *pdev; + struct resource *res; + resource_size_t base, irq; + + pdev = &omap_i2c_devices[bus_id - 1]; + if (bus_id == 1) { + res = pdev->resource; + if (cpu_class_is_omap1()) { + base = OMAP1_I2C_BASE; + irq = INT_I2C; + } else { + base = OMAP2_I2C_BASE1; + irq = INT_24XX_I2C1_IRQ; + } + res[0].start = base; + res[0].end = base + OMAP_I2C_SIZE; + res[1].start = irq; + } + + omap_i2c_mux_pins(bus_id - 1); + return platform_device_register(pdev); +} + /** * omap_i2c_bus_setup - Process command line options for the I2C bus speed * @str: String of options @@ -154,11 +181,33 @@ static int __init omap_i2c_bus_setup(char *str) if (ints[0] < 2 || ints[1] < 1 || ints[1] > ports) return 0; i2c_rate[ints[1] - 1] = ints[2]; + i2c_rate[ints[1] - 1] |= OMAP_I2C_CMDLINE_SETUP; return 1; } __setup("i2c_bus=", omap_i2c_bus_setup); +/* + * Register busses defined in command line but that are not registered with + * omap_register_i2c_bus from board initialization code. + */ +static int __init omap_register_i2c_bus_cmdline(void) +{ + int i, err = 0; + + for (i = 0; i < ARRAY_SIZE(i2c_rate); i++) + if (i2c_rate[i] & OMAP_I2C_CMDLINE_SETUP) { + i2c_rate[i] &= ~OMAP_I2C_CMDLINE_SETUP; + err = omap_i2c_add_bus(i + 1); + if (err) + goto out; + } + +out: + return err; +} +subsys_initcall(omap_register_i2c_bus_cmdline); + /** * omap_register_i2c_bus - register I2C bus with device descriptors * @bus_id: bus id counting from number 1 @@ -173,9 +222,6 @@ int __init omap_register_i2c_bus(int bus_id, u32 clkrate, unsigned len) { int err; - struct platform_device *pdev; - struct resource *res; - resource_size_t base, irq; BUG_ON(bus_id < 1 || bus_id > omap_i2c_nr_ports()); @@ -185,24 +231,9 @@ int __init omap_register_i2c_bus(int bus_id, u32 clkrate, return err; } - pdev = &omap_i2c_devices[bus_id - 1]; - if (i2c_rate[bus_id - 1] == 0) + if (!i2c_rate[bus_id - 1]) i2c_rate[bus_id - 1] = clkrate; + i2c_rate[bus_id - 1] &= ~OMAP_I2C_CMDLINE_SETUP; - if (bus_id == 1) { - res = pdev->resource; - if (cpu_class_is_omap1()) { - base = OMAP1_I2C_BASE; - irq = INT_I2C; - } else { - base = OMAP2_I2C_BASE1; - irq = INT_24XX_I2C1_IRQ; - } - res[0].start = base; - res[0].end = base + OMAP_I2C_SIZE; - res[1].start = irq; - } - - omap_i2c_mux_pins(bus_id - 1); - return platform_device_register(pdev); + return omap_i2c_add_bus(bus_id); } -- 2.39.5