From e4ff525f91f813456cf42a29227ee4a0fe01788b Mon Sep 17 00:00:00 2001 From: Troy Kisky Date: Thu, 19 Jul 2012 08:18:18 +0000 Subject: mxc_i2c: prep work for multiple busses support Signed-off-by: Troy Kisky --- drivers/i2c/mxc_i2c.c | 125 +++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 104 insertions(+), 21 deletions(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/mxc_i2c.c b/drivers/i2c/mxc_i2c.c index 44a04b57d6..ead6e209b2 100644 --- a/drivers/i2c/mxc_i2c.c +++ b/drivers/i2c/mxc_i2c.c @@ -59,9 +59,7 @@ struct mxc_i2c_regs { #define I2SR_IIF (1 << 1) #define I2SR_RX_NO_AK (1 << 0) -#ifdef CONFIG_SYS_I2C_BASE -#define I2C_BASE CONFIG_SYS_I2C_BASE -#else +#if defined(CONFIG_HARD_I2C) && !defined(CONFIG_SYS_I2C_BASE) #error "define CONFIG_SYS_I2C_BASE to use the mxc_i2c driver" #endif @@ -115,11 +113,11 @@ static uint8_t i2c_imx_get_clk(unsigned int rate) } /* - * Init I2C Bus + * Set I2C Bus speed */ -void i2c_init(int speed, int unused) +int bus_i2c_set_bus_speed(void *base, int speed) { - struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE; + struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base; u8 clk_idx = i2c_imx_get_clk(speed); u8 idx = i2c_clk_div[clk_idx][1]; @@ -129,23 +127,15 @@ void i2c_init(int speed, int unused) /* Reset module */ writeb(0, &i2c_regs->i2cr); writeb(0, &i2c_regs->i2sr); -} - -/* - * Set I2C Speed - */ -int i2c_set_bus_speed(unsigned int speed) -{ - i2c_init(speed, 0); return 0; } /* * Get I2C Speed */ -unsigned int i2c_get_bus_speed(void) +unsigned int bus_i2c_get_bus_speed(void *base) { - struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE; + struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base; u8 clk_idx = readb(&i2c_regs->ifdr); u8 clk_div; @@ -287,12 +277,13 @@ static int i2c_init_transfer(struct mxc_i2c_regs *i2c_regs, /* * Read data from I2C device */ -int i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len) +int bus_i2c_read(void *base, uchar chip, uint addr, int alen, uchar *buf, + int len) { - struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE; int ret; unsigned int temp; int i; + struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base; ret = i2c_init_transfer(i2c_regs, chip, addr, alen); if (ret < 0) @@ -346,11 +337,12 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len) /* * Write data to I2C device */ -int i2c_write(uchar chip, uint addr, int alen, uchar *buf, int len) +int bus_i2c_write(void *base, uchar chip, uint addr, int alen, + const uchar *buf, int len) { - struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE; int ret; int i; + struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base; ret = i2c_init_transfer(i2c_regs, chip, addr, alen); if (ret < 0) @@ -365,10 +357,101 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buf, int len) return ret; } +struct i2c_parms { + void *base; + void *idle_bus_data; + int (*idle_bus_fn)(void *p); +}; + +struct sram_data { + unsigned curr_i2c_bus; + struct i2c_parms i2c_data[3]; +}; + +/* + * For SPL boot some boards need i2c before SDRAM is initialized so force + * variables to live in SRAM + */ +static struct sram_data __attribute__((section(".data"))) srdata; + +void *get_base(void) +{ +#ifdef CONFIG_SYS_I2C_BASE +#ifdef CONFIG_I2C_MULTI_BUS + void *ret = srdata.i2c_data[srdata.curr_i2c_bus].base; + if (ret) + return ret; +#endif + return (void *)CONFIG_SYS_I2C_BASE; +#elif defined(CONFIG_I2C_MULTI_BUS) + return srdata.i2c_data[srdata.curr_i2c_bus].base; +#else + return srdata.i2c_data[0].base; +#endif +} + +int i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len) +{ + return bus_i2c_read(get_base(), chip, addr, alen, buf, len); +} + +int i2c_write(uchar chip, uint addr, int alen, uchar *buf, int len) +{ + return bus_i2c_write(get_base(), chip, addr, alen, buf, len); +} + /* * Test if a chip at a given address responds (probe the chip) */ int i2c_probe(uchar chip) { - return i2c_write(chip, 0, 0, NULL, 0); + return bus_i2c_write(get_base(), chip, 0, 0, NULL, 0); +} + +void bus_i2c_init(void *base, int speed, int unused, + int (*idle_bus_fn)(void *p), void *idle_bus_data) +{ + int i = 0; + struct i2c_parms *p = srdata.i2c_data; + if (!base) + return; + for (;;) { + if (!p->base || (p->base == base)) { + p->base = base; + if (idle_bus_fn) { + p->idle_bus_fn = idle_bus_fn; + p->idle_bus_data = idle_bus_data; + } + break; + } + p++; + i++; + if (i >= ARRAY_SIZE(srdata.i2c_data)) + return; + } + bus_i2c_set_bus_speed(base, speed); +} + +/* + * Init I2C Bus + */ +void i2c_init(int speed, int unused) +{ + bus_i2c_init(get_base(), speed, unused, NULL, NULL); +} + +/* + * Set I2C Speed + */ +int i2c_set_bus_speed(unsigned int speed) +{ + return bus_i2c_set_bus_speed(get_base(), speed); +} + +/* + * Get I2C Speed + */ +unsigned int i2c_get_bus_speed(void) +{ + return bus_i2c_get_bus_speed(get_base()); } -- cgit v1.2.1