[U-Boot] [PATCH] i2c: mxs: Add I2C multibus support

[Heiko Schocher]

Hello Marek,

Am 23.09.2014 13:15, schrieb Marek Vasut:
> The i.MX28 has two I2C IP blocks, but the MXS I2C driver is hard-coded
> to use the I2C block 0 . Add multibus support so we can use both I2C
> busses as seen fit.
>
> Signed-off-by: Marek Vasut<marex at denx.de>
> Cc: Stefano Babic<sbabic at denx.de>
> ---
>   drivers/i2c/mxs_i2c.c | 47 +++++++++++++++++++++++++++++++++++++----------
>   include/configs/mxs.h |  1 +
>   2 files changed, 38 insertions(+), 10 deletions(-)

Sorry, I have to NACK this patch. Please convert the driver for using
the CONFIG_SYS_I2C framework, see for example the drivers/i2c/mxc_i2c.c
driver, thanks!

bye,
Heiko
>
> diff --git a/drivers/i2c/mxs_i2c.c b/drivers/i2c/mxs_i2c.c
> index de3b194..989cf07 100644
> --- a/drivers/i2c/mxs_i2c.c
> +++ b/drivers/i2c/mxs_i2c.c
> @@ -24,9 +24,12 @@
>
>   #define	MXS_I2C_MAX_TIMEOUT	1000000
>
> +static struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
> +static int mxs_i2c_bus;
> +static int mxs_i2c_speed = CONFIG_SYS_I2C_SPEED;
> +
>   static void mxs_i2c_reset(void)
>   {
> -	struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
>   	int ret;
>   	int speed = i2c_get_bus_speed();
>
> @@ -48,8 +51,6 @@ static void mxs_i2c_reset(void)
>
>   static void mxs_i2c_setup_read(uint8_t chip, int len)
>   {
> -	struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
> -
>   	writel(I2C_QUEUECMD_RETAIN_CLOCK | I2C_QUEUECMD_PRE_SEND_START |
>   		I2C_QUEUECMD_MASTER_MODE | I2C_QUEUECMD_DIRECTION |
>   		(1<<  I2C_QUEUECMD_XFER_COUNT_OFFSET),
> @@ -67,7 +68,6 @@ static void mxs_i2c_setup_read(uint8_t chip, int len)
>   static int mxs_i2c_write(uchar chip, uint addr, int alen,
>   			uchar *buf, int blen, int stop)
>   {
> -	struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
>   	uint32_t data, tmp;
>   	int i, remain, off;
>   	int timeout = MXS_I2C_MAX_TIMEOUT;
> @@ -124,7 +124,6 @@ static int mxs_i2c_write(uchar chip, uint addr, int alen,
>
>   static int mxs_i2c_wait_for_ack(void)
>   {
> -	struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
>   	uint32_t tmp;
>   	int timeout = MXS_I2C_MAX_TIMEOUT;
>
> @@ -162,7 +161,6 @@ err:
>
>   int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
>   {
> -	struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
>   	uint32_t tmp = 0;
>   	int timeout = MXS_I2C_MAX_TIMEOUT;
>   	int ret;
> @@ -237,7 +235,6 @@ int i2c_probe(uchar chip)
>
>   int i2c_set_bus_speed(unsigned int speed)
>   {
> -	struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
>   	/*
>   	 * The timing derivation algorithm. There is no documentation for this
>   	 * algorithm available, it was derived by using the scope and fiddling
> @@ -278,7 +275,6 @@ int i2c_set_bus_speed(unsigned int speed)
>
>   unsigned int i2c_get_bus_speed(void)
>   {
> -	struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
>   	uint32_t clk = mxc_get_clock(MXC_XTAL_CLK);
>   	uint32_t timing0;
>
> @@ -290,10 +286,41 @@ unsigned int i2c_get_bus_speed(void)
>   	return clk / ((((timing0>>  16) - 3) * 2) + 38);
>   }
>
> -void i2c_init(int speed, int slaveadd)
> +int i2c_set_bus_num(unsigned int bus)
>   {
> +	uint32_t mxs_i2c_regs;
> +
> +	switch (bus) {
> +	case 0:
> +		mxs_i2c_regs = MXS_I2C0_BASE;
> +		break;
> +#ifdef CONFIG_MX28
> +	case 1:
> +		mxs_i2c_regs = MXS_I2C1_BASE;
> +		break;
> +#endif
> +	default:
> +		printf("Bad bus: %d\n", bus);
> +		return -EINVAL;
> +	}
> +
> +	mxs_i2c_bus = bus;
> +	i2c_regs = (struct mxs_i2c_regs *)mxs_i2c_regs;
> +
>   	mxs_i2c_reset();
> -	i2c_set_bus_speed(speed);
> +	i2c_set_bus_speed(mxs_i2c_speed);
>
> +	return 0;
> +}
> +
> +unsigned int i2c_get_bus_num(void)
> +{
> +	return mxs_i2c_bus;
> +}
> +
> +void i2c_init(int speed, int slaveadd)
> +{
> +	mxs_i2c_speed = speed;
> +	i2c_set_bus_num(0);
>   	return;
>   }
> diff --git a/include/configs/mxs.h b/include/configs/mxs.h
> index eb96fc1..3936029 100644
> --- a/include/configs/mxs.h
> +++ b/include/configs/mxs.h
> @@ -149,6 +149,7 @@
>   /* I2C */
>   #ifdef CONFIG_CMD_I2C
>   #define CONFIG_I2C_MXS
> +#define CONFIG_I2C_MULTI_BUS
>   #define CONFIG_HARD_I2C
>   #ifndef CONFIG_SYS_I2C_SPEED
>   #define CONFIG_SYS_I2C_SPEED		400000

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