Commit 962b6032 authored by Magnus Damm's avatar Magnus Damm Committed by Paul Mundt
Browse files

i2c: i2c-sh_mobile support for new ICIC bits 



Add support for a new version of the IIC block
found in the SH-Mobile ARM line of processors.

Prototype patch written by Nishimoto-san.
Tested on sh7377 and sh7372.

Signed-off-by: default avatarNISHIMOTO Hiroki <nishimoto.hiroki@renesas.com>
Signed-off-by: default avatarMagnus Damm <damm@opensource.se>
Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
parent 12a55f2d

drivers/i2c/busses/i2c-sh_mobile.c

+31 −0
Original line number Diff line number Diff line
@@ -119,8 +119,10 @@ struct sh_mobile_i2c_data { 
	struct i2c_adapter adap;



	struct clk *clk;

	u_int8_t icic;

	u_int8_t iccl;

	u_int8_t icch;

	u_int8_t flags;



	spinlock_t lock;

	wait_queue_head_t wait;
@@ -129,6 +131,8 @@ struct sh_mobile_i2c_data { 
	int sr;

};



#define IIC_FLAG_HAS_ICIC67	(1 << 0)



#define NORMAL_SPEED		100000 /* FAST_SPEED 400000 */



/* Register offsets */
@@ -155,6 +159,8 @@ struct sh_mobile_i2c_data { 
#define ICSR_WAIT		0x02

#define ICSR_DTE		0x01



#define ICIC_ICCLB8		0x80

#define ICIC_ICCHB8		0x40

#define ICIC_ALE		0x08

#define ICIC_TACKE		0x04

#define ICIC_WAITE		0x02
@@ -162,6 +168,9 @@ struct sh_mobile_i2c_data { 


static void iic_wr(struct sh_mobile_i2c_data *pd, int offs, unsigned char data)

{

	if (offs == ICIC)

		data |= pd->icic;



	iowrite8(data, pd->reg + offs);

}
@@ -203,6 +212,14 @@ static void activate_ch(struct sh_mobile_i2c_data *pd) 
	else

		pd->iccl = (u_int8_t)(num/denom);



	/* one more bit of ICCL in ICIC */

	if (pd->flags & IIC_FLAG_HAS_ICIC67) {

		if ((num/denom) > 0xff)

			pd->icic |= ICIC_ICCLB8;

		else

			pd->icic &= ~ICIC_ICCLB8;

	}



	/* Calculate the value for icch. From the data sheet:

	   icch = (p clock / transfer rate) * (H / (L + H)) */

	num = i2c_clk * 4;
@@ -212,6 +229,14 @@ static void activate_ch(struct sh_mobile_i2c_data *pd) 
	else

		pd->icch = (u_int8_t)(num/denom);



	/* one more bit of ICCH in ICIC */

	if (pd->flags & IIC_FLAG_HAS_ICIC67) {

		if ((num/denom) > 0xff)

			pd->icic |= ICIC_ICCHB8;

		else

			pd->icic &= ~ICIC_ICCHB8;

	}



	/* Enable channel and configure rx ack */

	iic_set_clr(pd, ICCR, ICCR_ICE, 0);
@@ -592,6 +617,12 @@ static int sh_mobile_i2c_probe(struct platform_device *dev) 
		goto err_irq;

	}



	/* The IIC blocks on SH-Mobile ARM processors

	 * come with two new bits in ICIC.

	 */

	if (size > 0x17)

		pd->flags |= IIC_FLAG_HAS_ICIC67;



	/* Enable Runtime PM for this device.

	 *

	 * Also tell the Runtime PM core to ignore children

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