On Wed, Sep 12, 2012 at 5:46 PM, Tetsuyuki Kobayashi koba@kmckk.co.jp wrote:
Before this patch i2c_probe() always returned 0 and "i2c probe" command did not work properly.
Modify i2c_set_addr() to check TACK when waiting DTE and make i2c_probe() call this function.
Signed-off-by: Tetsuyuki Kobayashi koba@kmckk.co.jp
Changes for v2:
- new
drivers/i2c/sh_i2c.c | 29 ++++++++++++++++++++++++----- 1 file changed, 24 insertions(+), 5 deletions(-)
diff --git a/drivers/i2c/sh_i2c.c b/drivers/i2c/sh_i2c.c index d524619..25dbc43 100644 --- a/drivers/i2c/sh_i2c.c +++ b/drivers/i2c/sh_i2c.c @@ -85,6 +85,21 @@ static void irq_dte(struct sh_i2c *base) } }
+static int irq_dte_with_tack(struct sh_i2c *base) +{
int i;int ret = 0;for (i = 0 ; i < IRQ_WAIT ; i++) {if (SH_IC_DTE & readb(&base->icsr))break;if (SH_IC_TACK & readb(&base->icsr))return -1;udelay(10);}return ret;+}
static void irq_busy(struct sh_i2c *base) { int i; @@ -96,9 +111,9 @@ static void irq_busy(struct sh_i2c *base) } }
-static void i2c_set_addr(struct sh_i2c *base, u8 id, u8 reg, int stop) +static int i2c_set_addr(struct sh_i2c *base, u8 id, u8 reg, int stop) {
u8 icic = 0;
u8 icic = SH_IC_TACK; writeb(readb(&base->iccr) & ~SH_I2C_ICCR_ICE, &base->iccr); writeb(readb(&base->iccr) | SH_I2C_ICCR_ICE, &base->iccr);@@ -116,14 +131,18 @@ static void i2c_set_addr(struct sh_i2c *base, u8 id, u8 reg, int stop) writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_RTS|SH_I2C_ICCR_BUSY), &base->iccr); irq_dte(base);
writeb(readb(&base->icsr) & ~SH_IC_TACK, &base->icsr); writeb(id << 1, &base->icdr);
irq_dte(base);
if (irq_dte_with_tack(base) != 0)return -1; writeb(reg, &base->icdr); if (stop) writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_RTS), &base->iccr);
irq_dte(base);
if (irq_dte_with_tack(base) != 0)return -1;return 0;}
static void i2c_finish(struct sh_i2c *base) @@ -321,5 +340,5 @@ int i2c_write(u8 chip, u32 addr, int alen, u8 *buffer, int len) */ int i2c_probe(u8 chip) {
return 0;
return i2c_set_addr(base, chip, 0, 1);}
1.7.9.5
Acked-by: Nobuhiro Iwamatsu nobuhiro.iwamatsu.yj@renesas.com
Best regards, Nobuhiro