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path: root/drivers/i2c/busses/i2c-sh_mobile.c
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-rw-r--r--drivers/i2c/busses/i2c-sh_mobile.c121
1 files changed, 84 insertions, 37 deletions
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index ffb405d7c6f2..598c49acaeb5 100644
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -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;
@@ -129,15 +131,17 @@ struct sh_mobile_i2c_data {
int sr;
};
+#define IIC_FLAG_HAS_ICIC67 (1 << 0)
+
#define NORMAL_SPEED 100000 /* FAST_SPEED 400000 */
/* Register offsets */
-#define ICDR(pd) (pd->reg + 0x00)
-#define ICCR(pd) (pd->reg + 0x04)
-#define ICSR(pd) (pd->reg + 0x08)
-#define ICIC(pd) (pd->reg + 0x0c)
-#define ICCL(pd) (pd->reg + 0x10)
-#define ICCH(pd) (pd->reg + 0x14)
+#define ICDR 0x00
+#define ICCR 0x04
+#define ICSR 0x08
+#define ICIC 0x0c
+#define ICCL 0x10
+#define ICCH 0x14
/* Register bits */
#define ICCR_ICE 0x80
@@ -155,11 +159,32 @@ 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
#define ICIC_DTEE 0x01
+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);
+}
+
+static unsigned char iic_rd(struct sh_mobile_i2c_data *pd, int offs)
+{
+ return ioread8(pd->reg + offs);
+}
+
+static void iic_set_clr(struct sh_mobile_i2c_data *pd, int offs,
+ unsigned char set, unsigned char clr)
+{
+ iic_wr(pd, offs, (iic_rd(pd, offs) | set) & ~clr);
+}
+
static void activate_ch(struct sh_mobile_i2c_data *pd)
{
unsigned long i2c_clk;
@@ -187,6 +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;
@@ -196,25 +229,33 @@ 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 */
- iowrite8(ioread8(ICCR(pd)) | ICCR_ICE, ICCR(pd));
+ iic_set_clr(pd, ICCR, ICCR_ICE, 0);
/* Mask all interrupts */
- iowrite8(0, ICIC(pd));
+ iic_wr(pd, ICIC, 0);
/* Set the clock */
- iowrite8(pd->iccl, ICCL(pd));
- iowrite8(pd->icch, ICCH(pd));
+ iic_wr(pd, ICCL, pd->iccl);
+ iic_wr(pd, ICCH, pd->icch);
}
static void deactivate_ch(struct sh_mobile_i2c_data *pd)
{
/* Clear/disable interrupts */
- iowrite8(0, ICSR(pd));
- iowrite8(0, ICIC(pd));
+ iic_wr(pd, ICSR, 0);
+ iic_wr(pd, ICIC, 0);
/* Disable channel */
- iowrite8(ioread8(ICCR(pd)) & ~ICCR_ICE, ICCR(pd));
+ iic_set_clr(pd, ICCR, 0, ICCR_ICE);
/* Disable clock and mark device as idle */
clk_disable(pd->clk);
@@ -233,35 +274,35 @@ static unsigned char i2c_op(struct sh_mobile_i2c_data *pd,
switch (op) {
case OP_START: /* issue start and trigger DTE interrupt */
- iowrite8(0x94, ICCR(pd));
+ iic_wr(pd, ICCR, 0x94);
break;
case OP_TX_FIRST: /* disable DTE interrupt and write data */
- iowrite8(ICIC_WAITE | ICIC_ALE | ICIC_TACKE, ICIC(pd));
- iowrite8(data, ICDR(pd));
+ iic_wr(pd, ICIC, ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
+ iic_wr(pd, ICDR, data);
break;
case OP_TX: /* write data */
- iowrite8(data, ICDR(pd));
+ iic_wr(pd, ICDR, data);
break;
case OP_TX_STOP: /* write data and issue a stop afterwards */
- iowrite8(data, ICDR(pd));
- iowrite8(0x90, ICCR(pd));
+ iic_wr(pd, ICDR, data);
+ iic_wr(pd, ICCR, 0x90);
break;
case OP_TX_TO_RX: /* select read mode */
- iowrite8(0x81, ICCR(pd));
+ iic_wr(pd, ICCR, 0x81);
break;
case OP_RX: /* just read data */
- ret = ioread8(ICDR(pd));
+ ret = iic_rd(pd, ICDR);
break;
case OP_RX_STOP: /* enable DTE interrupt, issue stop */
- iowrite8(ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE,
- ICIC(pd));
- iowrite8(0xc0, ICCR(pd));
+ iic_wr(pd, ICIC,
+ ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
+ iic_wr(pd, ICCR, 0xc0);
break;
case OP_RX_STOP_DATA: /* enable DTE interrupt, read data, issue stop */
- iowrite8(ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE,
- ICIC(pd));
- ret = ioread8(ICDR(pd));
- iowrite8(0xc0, ICCR(pd));
+ iic_wr(pd, ICIC,
+ ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
+ ret = iic_rd(pd, ICDR);
+ iic_wr(pd, ICCR, 0xc0);
break;
}
@@ -367,7 +408,7 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id)
unsigned char sr;
int wakeup;
- sr = ioread8(ICSR(pd));
+ sr = iic_rd(pd, ICSR);
pd->sr |= sr; /* remember state */
dev_dbg(pd->dev, "i2c_isr 0x%02x 0x%02x %s %d %d!\n", sr, pd->sr,
@@ -376,7 +417,7 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id)
if (sr & (ICSR_AL | ICSR_TACK)) {
/* don't interrupt transaction - continue to issue stop */
- iowrite8(sr & ~(ICSR_AL | ICSR_TACK), ICSR(pd));
+ iic_wr(pd, ICSR, sr & ~(ICSR_AL | ICSR_TACK));
wakeup = 0;
} else if (pd->msg->flags & I2C_M_RD)
wakeup = sh_mobile_i2c_isr_rx(pd);
@@ -384,7 +425,7 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id)
wakeup = sh_mobile_i2c_isr_tx(pd);
if (sr & ICSR_WAIT) /* TODO: add delay here to support slow acks */
- iowrite8(sr & ~ICSR_WAIT, ICSR(pd));
+ iic_wr(pd, ICSR, sr & ~ICSR_WAIT);
if (wakeup) {
pd->sr |= SW_DONE;
@@ -402,21 +443,21 @@ static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg)
}
/* Initialize channel registers */
- iowrite8(ioread8(ICCR(pd)) & ~ICCR_ICE, ICCR(pd));
+ iic_set_clr(pd, ICCR, 0, ICCR_ICE);
/* Enable channel and configure rx ack */
- iowrite8(ioread8(ICCR(pd)) | ICCR_ICE, ICCR(pd));
+ iic_set_clr(pd, ICCR, ICCR_ICE, 0);
/* Set the clock */
- iowrite8(pd->iccl, ICCL(pd));
- iowrite8(pd->icch, ICCH(pd));
+ iic_wr(pd, ICCL, pd->iccl);
+ iic_wr(pd, ICCH, pd->icch);
pd->msg = usr_msg;
pd->pos = -1;
pd->sr = 0;
/* Enable all interrupts to begin with */
- iowrite8(ICIC_WAITE | ICIC_ALE | ICIC_TACKE | ICIC_DTEE, ICIC(pd));
+ iic_wr(pd, ICIC, ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE);
return 0;
}
@@ -451,7 +492,7 @@ static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter,
retry_count = 1000;
again:
- val = ioread8(ICSR(pd));
+ val = iic_rd(pd, ICSR);
dev_dbg(pd->dev, "val 0x%02x pd->sr 0x%02x\n", val, pd->sr);
@@ -576,6 +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
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.