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-rw-r--r--drivers/i2c/busses/i2c-pxa.c94
-rw-r--r--drivers/i2c/busses/i2c-sh_mobile.c271
2 files changed, 285 insertions, 80 deletions
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 44d838410f1..906f9b9d715 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -38,7 +38,44 @@
#include <asm/irq.h>
#include <asm/io.h>
#include <mach/i2c.h>
-#include <mach/pxa-regs.h>
+
+/*
+ * I2C registers and bit definitions
+ */
+#define IBMR (0x00)
+#define IDBR (0x08)
+#define ICR (0x10)
+#define ISR (0x18)
+#define ISAR (0x20)
+
+#define ICR_START (1 << 0) /* start bit */
+#define ICR_STOP (1 << 1) /* stop bit */
+#define ICR_ACKNAK (1 << 2) /* send ACK(0) or NAK(1) */
+#define ICR_TB (1 << 3) /* transfer byte bit */
+#define ICR_MA (1 << 4) /* master abort */
+#define ICR_SCLE (1 << 5) /* master clock enable */
+#define ICR_IUE (1 << 6) /* unit enable */
+#define ICR_GCD (1 << 7) /* general call disable */
+#define ICR_ITEIE (1 << 8) /* enable tx interrupts */
+#define ICR_IRFIE (1 << 9) /* enable rx interrupts */
+#define ICR_BEIE (1 << 10) /* enable bus error ints */
+#define ICR_SSDIE (1 << 11) /* slave STOP detected int enable */
+#define ICR_ALDIE (1 << 12) /* enable arbitration interrupt */
+#define ICR_SADIE (1 << 13) /* slave address detected int enable */
+#define ICR_UR (1 << 14) /* unit reset */
+#define ICR_FM (1 << 15) /* fast mode */
+
+#define ISR_RWM (1 << 0) /* read/write mode */
+#define ISR_ACKNAK (1 << 1) /* ack/nak status */
+#define ISR_UB (1 << 2) /* unit busy */
+#define ISR_IBB (1 << 3) /* bus busy */
+#define ISR_SSD (1 << 4) /* slave stop detected */
+#define ISR_ALD (1 << 5) /* arbitration loss detected */
+#define ISR_ITE (1 << 6) /* tx buffer empty */
+#define ISR_IRF (1 << 7) /* rx buffer full */
+#define ISR_GCAD (1 << 8) /* general call address detected */
+#define ISR_SAD (1 << 9) /* slave address detected */
+#define ISR_BED (1 << 10) /* bus error no ACK/NAK */
struct pxa_i2c {
spinlock_t lock;
@@ -60,19 +97,21 @@ struct pxa_i2c {
u32 icrlog[32];
void __iomem *reg_base;
+ unsigned int reg_shift;
unsigned long iobase;
unsigned long iosize;
int irq;
- int use_pio;
+ unsigned int use_pio :1;
+ unsigned int fast_mode :1;
};
-#define _IBMR(i2c) ((i2c)->reg_base + 0)
-#define _IDBR(i2c) ((i2c)->reg_base + 8)
-#define _ICR(i2c) ((i2c)->reg_base + 0x10)
-#define _ISR(i2c) ((i2c)->reg_base + 0x18)
-#define _ISAR(i2c) ((i2c)->reg_base + 0x20)
+#define _IBMR(i2c) ((i2c)->reg_base + (0x0 << (i2c)->reg_shift))
+#define _IDBR(i2c) ((i2c)->reg_base + (0x4 << (i2c)->reg_shift))
+#define _ICR(i2c) ((i2c)->reg_base + (0x8 << (i2c)->reg_shift))
+#define _ISR(i2c) ((i2c)->reg_base + (0xc << (i2c)->reg_shift))
+#define _ISAR(i2c) ((i2c)->reg_base + (0x10 << (i2c)->reg_shift))
/*
* I2C Slave mode address
@@ -188,14 +227,14 @@ static inline int i2c_pxa_is_slavemode(struct pxa_i2c *i2c)
static void i2c_pxa_abort(struct pxa_i2c *i2c)
{
- unsigned long timeout = jiffies + HZ/4;
+ int i = 250;
if (i2c_pxa_is_slavemode(i2c)) {
dev_dbg(&i2c->adap.dev, "%s: called in slave mode\n", __func__);
return;
}
- while (time_before(jiffies, timeout) && (readl(_IBMR(i2c)) & 0x1) == 0) {
+ while ((i > 0) && (readl(_IBMR(i2c)) & 0x1) == 0) {
unsigned long icr = readl(_ICR(i2c));
icr &= ~ICR_START;
@@ -205,7 +244,8 @@ static void i2c_pxa_abort(struct pxa_i2c *i2c)
show_state(i2c);
- msleep(1);
+ mdelay(1);
+ i --;
}
writel(readl(_ICR(i2c)) & ~(ICR_MA | ICR_START | ICR_STOP),
@@ -364,7 +404,7 @@ static void i2c_pxa_reset(struct pxa_i2c *i2c)
writel(i2c->slave_addr, _ISAR(i2c));
/* set control register values */
- writel(I2C_ICR_INIT, _ICR(i2c));
+ writel(I2C_ICR_INIT | (i2c->fast_mode ? ICR_FM : 0), _ICR(i2c));
#ifdef CONFIG_I2C_PXA_SLAVE
dev_info(&i2c->adap.dev, "Enabling slave mode\n");
@@ -907,12 +947,6 @@ static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num
struct pxa_i2c *i2c = adap->algo_data;
int ret, i;
- /* If the I2C controller is disabled we need to reset it (probably due
- to a suspend/resume destroying state). We do this here as we can then
- avoid worrying about resuming the controller before its users. */
- if (!(readl(_ICR(i2c)) & ICR_IUE))
- i2c_pxa_reset(i2c);
-
for (i = adap->retries; i >= 0; i--) {
ret = i2c_pxa_do_xfer(i2c, msgs, num);
if (ret != I2C_RETRY)
@@ -993,6 +1027,7 @@ static int i2c_pxa_probe(struct platform_device *dev)
ret = -EIO;
goto eremap;
}
+ i2c->reg_shift = (cpu_is_pxa3xx() && (dev->id == 1)) ? 0 : 1;
i2c->iobase = res->start;
i2c->iosize = res_len(res);
@@ -1013,6 +1048,7 @@ static int i2c_pxa_probe(struct platform_device *dev)
if (plat) {
i2c->adap.class = plat->class;
i2c->use_pio = plat->use_pio;
+ i2c->fast_mode = plat->fast_mode;
}
if (i2c->use_pio) {
@@ -1082,9 +1118,33 @@ static int __exit i2c_pxa_remove(struct platform_device *dev)
return 0;
}
+#ifdef CONFIG_PM
+static int i2c_pxa_suspend_late(struct platform_device *dev, pm_message_t state)
+{
+ struct pxa_i2c *i2c = platform_get_drvdata(dev);
+ clk_disable(i2c->clk);
+ return 0;
+}
+
+static int i2c_pxa_resume_early(struct platform_device *dev)
+{
+ struct pxa_i2c *i2c = platform_get_drvdata(dev);
+
+ clk_enable(i2c->clk);
+ i2c_pxa_reset(i2c);
+
+ return 0;
+}
+#else
+#define i2c_pxa_suspend_late NULL
+#define i2c_pxa_resume_early NULL
+#endif
+
static struct platform_driver i2c_pxa_driver = {
.probe = i2c_pxa_probe,
.remove = __exit_p(i2c_pxa_remove),
+ .suspend_late = i2c_pxa_suspend_late,
+ .resume_early = i2c_pxa_resume_early,
.driver = {
.name = "pxa2xx-i2c",
.owner = THIS_MODULE,
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index 840e634fa31..640cbb23732 100644
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -31,13 +31,84 @@
#include <linux/clk.h>
#include <linux/io.h>
+/* Transmit operation: */
+/* */
+/* 0 byte transmit */
+/* BUS: S A8 ACK P */
+/* IRQ: DTE WAIT */
+/* ICIC: */
+/* ICCR: 0x94 0x90 */
+/* ICDR: A8 */
+/* */
+/* 1 byte transmit */
+/* BUS: S A8 ACK D8(1) ACK P */
+/* IRQ: DTE WAIT WAIT */
+/* ICIC: -DTE */
+/* ICCR: 0x94 0x90 */
+/* ICDR: A8 D8(1) */
+/* */
+/* 2 byte transmit */
+/* BUS: S A8 ACK D8(1) ACK D8(2) ACK P */
+/* IRQ: DTE WAIT WAIT WAIT */
+/* ICIC: -DTE */
+/* ICCR: 0x94 0x90 */
+/* ICDR: A8 D8(1) D8(2) */
+/* */
+/* 3 bytes or more, +---------+ gets repeated */
+/* */
+/* */
+/* Receive operation: */
+/* */
+/* 0 byte receive - not supported since slave may hold SDA low */
+/* */
+/* 1 byte receive [TX] | [RX] */
+/* BUS: S A8 ACK | D8(1) ACK P */
+/* IRQ: DTE WAIT | WAIT DTE */
+/* ICIC: -DTE | +DTE */
+/* ICCR: 0x94 0x81 | 0xc0 */
+/* ICDR: A8 | D8(1) */
+/* */
+/* 2 byte receive [TX]| [RX] */
+/* BUS: S A8 ACK | D8(1) ACK D8(2) ACK P */
+/* IRQ: DTE WAIT | WAIT WAIT DTE */
+/* ICIC: -DTE | +DTE */
+/* ICCR: 0x94 0x81 | 0xc0 */
+/* ICDR: A8 | D8(1) D8(2) */
+/* */
+/* 3 byte receive [TX] | [RX] */
+/* BUS: S A8 ACK | D8(1) ACK D8(2) ACK D8(3) ACK P */
+/* IRQ: DTE WAIT | WAIT WAIT WAIT DTE */
+/* ICIC: -DTE | +DTE */
+/* ICCR: 0x94 0x81 | 0xc0 */
+/* ICDR: A8 | D8(1) D8(2) D8(3) */
+/* */
+/* 4 bytes or more, this part is repeated +---------+ */
+/* */
+/* */
+/* Interrupt order and BUSY flag */
+/* ___ _ */
+/* SDA ___\___XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXAAAAAAAAA___/ */
+/* SCL \_/1\_/2\_/3\_/4\_/5\_/6\_/7\_/8\___/9\_____/ */
+/* */
+/* S D7 D6 D5 D4 D3 D2 D1 D0 P */
+/* ___ */
+/* WAIT IRQ ________________________________/ \___________ */
+/* TACK IRQ ____________________________________/ \_______ */
+/* DTE IRQ __________________________________________/ \_ */
+/* AL IRQ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */
+/* _______________________________________________ */
+/* BUSY __/ \_ */
+/* */
+
enum sh_mobile_i2c_op {
OP_START = 0,
- OP_TX_ONLY,
+ OP_TX_FIRST,
+ OP_TX,
OP_TX_STOP,
OP_TX_TO_RX,
- OP_RX_ONLY,
+ OP_RX,
OP_RX_STOP,
+ OP_RX_STOP_DATA,
};
struct sh_mobile_i2c_data {
@@ -127,25 +198,34 @@ static unsigned char i2c_op(struct sh_mobile_i2c_data *pd,
spin_lock_irqsave(&pd->lock, flags);
switch (op) {
- case OP_START:
+ case OP_START: /* issue start and trigger DTE interrupt */
iowrite8(0x94, ICCR(pd));
break;
- case OP_TX_ONLY:
+ case OP_TX_FIRST: /* disable DTE interrupt and write data */
+ iowrite8(ICIC_WAITE | ICIC_ALE | ICIC_TACKE, ICIC(pd));
iowrite8(data, ICDR(pd));
break;
- case OP_TX_STOP:
+ case OP_TX: /* write data */
iowrite8(data, ICDR(pd));
- iowrite8(0x90, ICCR(pd));
- iowrite8(ICIC_ALE | ICIC_TACKE, ICIC(pd));
break;
- case OP_TX_TO_RX:
+ case OP_TX_STOP: /* write data and issue a stop afterwards */
iowrite8(data, ICDR(pd));
+ iowrite8(0x90, ICCR(pd));
+ break;
+ case OP_TX_TO_RX: /* select read mode */
iowrite8(0x81, ICCR(pd));
break;
- case OP_RX_ONLY:
+ case OP_RX: /* just read data */
ret = ioread8(ICDR(pd));
break;
- case OP_RX_STOP:
+ case OP_RX_STOP: /* enable DTE interrupt, issue stop */
+ iowrite8(ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE,
+ ICIC(pd));
+ iowrite8(0xc0, ICCR(pd));
+ 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));
break;
@@ -157,58 +237,120 @@ static unsigned char i2c_op(struct sh_mobile_i2c_data *pd,
return ret;
}
+static int sh_mobile_i2c_is_first_byte(struct sh_mobile_i2c_data *pd)
+{
+ if (pd->pos == -1)
+ return 1;
+
+ return 0;
+}
+
+static int sh_mobile_i2c_is_last_byte(struct sh_mobile_i2c_data *pd)
+{
+ if (pd->pos == (pd->msg->len - 1))
+ return 1;
+
+ return 0;
+}
+
+static void sh_mobile_i2c_get_data(struct sh_mobile_i2c_data *pd,
+ unsigned char *buf)
+{
+ switch (pd->pos) {
+ case -1:
+ *buf = (pd->msg->addr & 0x7f) << 1;
+ *buf |= (pd->msg->flags & I2C_M_RD) ? 1 : 0;
+ break;
+ default:
+ *buf = pd->msg->buf[pd->pos];
+ }
+}
+
+static int sh_mobile_i2c_isr_tx(struct sh_mobile_i2c_data *pd)
+{
+ unsigned char data;
+
+ if (pd->pos == pd->msg->len)
+ return 1;
+
+ sh_mobile_i2c_get_data(pd, &data);
+
+ if (sh_mobile_i2c_is_last_byte(pd))
+ i2c_op(pd, OP_TX_STOP, data);
+ else if (sh_mobile_i2c_is_first_byte(pd))
+ i2c_op(pd, OP_TX_FIRST, data);
+ else
+ i2c_op(pd, OP_TX, data);
+
+ pd->pos++;
+ return 0;
+}
+
+static int sh_mobile_i2c_isr_rx(struct sh_mobile_i2c_data *pd)
+{
+ unsigned char data;
+ int real_pos;
+
+ do {
+ if (pd->pos <= -1) {
+ sh_mobile_i2c_get_data(pd, &data);
+
+ if (sh_mobile_i2c_is_first_byte(pd))
+ i2c_op(pd, OP_TX_FIRST, data);
+ else
+ i2c_op(pd, OP_TX, data);
+ break;
+ }
+
+ if (pd->pos == 0) {
+ i2c_op(pd, OP_TX_TO_RX, 0);
+ break;
+ }
+
+ real_pos = pd->pos - 2;
+
+ if (pd->pos == pd->msg->len) {
+ if (real_pos < 0) {
+ i2c_op(pd, OP_RX_STOP, 0);
+ break;
+ }
+ data = i2c_op(pd, OP_RX_STOP_DATA, 0);
+ } else
+ data = i2c_op(pd, OP_RX, 0);
+
+ pd->msg->buf[real_pos] = data;
+ } while (0);
+
+ pd->pos++;
+ return pd->pos == (pd->msg->len + 2);
+}
+
static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id)
{
struct platform_device *dev = dev_id;
struct sh_mobile_i2c_data *pd = platform_get_drvdata(dev);
- struct i2c_msg *msg = pd->msg;
- unsigned char data, sr;
- int wakeup = 0;
+ unsigned char sr;
+ int wakeup;
sr = ioread8(ICSR(pd));
- pd->sr |= sr;
+ pd->sr |= sr; /* remember state */
dev_dbg(pd->dev, "i2c_isr 0x%02x 0x%02x %s %d %d!\n", sr, pd->sr,
- (msg->flags & I2C_M_RD) ? "read" : "write",
- pd->pos, msg->len);
+ (pd->msg->flags & I2C_M_RD) ? "read" : "write",
+ pd->pos, pd->msg->len);
if (sr & (ICSR_AL | ICSR_TACK)) {
- iowrite8(0, ICIC(pd)); /* disable interrupts */
- wakeup = 1;
- goto do_wakeup;
- }
+ /* don't interrupt transaction - continue to issue stop */
+ iowrite8(sr & ~(ICSR_AL | ICSR_TACK), ICSR(pd));
+ wakeup = 0;
+ } else if (pd->msg->flags & I2C_M_RD)
+ wakeup = sh_mobile_i2c_isr_rx(pd);
+ else
+ wakeup = sh_mobile_i2c_isr_tx(pd);
- if (pd->pos == msg->len) {
- i2c_op(pd, OP_RX_ONLY, 0);
- wakeup = 1;
- goto do_wakeup;
- }
+ if (sr & ICSR_WAIT) /* TODO: add delay here to support slow acks */
+ iowrite8(sr & ~ICSR_WAIT, ICSR(pd));
- if (pd->pos == -1) {
- data = (msg->addr & 0x7f) << 1;
- data |= (msg->flags & I2C_M_RD) ? 1 : 0;
- } else
- data = msg->buf[pd->pos];
-
- if ((pd->pos == -1) || !(msg->flags & I2C_M_RD)) {
- if (msg->flags & I2C_M_RD)
- i2c_op(pd, OP_TX_TO_RX, data);
- else if (pd->pos == (msg->len - 1)) {
- i2c_op(pd, OP_TX_STOP, data);
- wakeup = 1;
- } else
- i2c_op(pd, OP_TX_ONLY, data);
- } else {
- if (pd->pos == (msg->len - 1))
- data = i2c_op(pd, OP_RX_STOP, 0);
- else
- data = i2c_op(pd, OP_RX_ONLY, 0);
-
- msg->buf[pd->pos] = data;
- }
- pd->pos++;
-
- do_wakeup:
if (wakeup) {
pd->sr |= SW_DONE;
wake_up(&pd->wait);
@@ -219,6 +361,11 @@ static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id)
static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg)
{
+ if (usr_msg->len == 0 && (usr_msg->flags & I2C_M_RD)) {
+ dev_err(pd->dev, "Unsupported zero length i2c read\n");
+ return -EIO;
+ }
+
/* Initialize channel registers */
iowrite8(ioread8(ICCR(pd)) & ~ICCR_ICE, ICCR(pd));
@@ -233,9 +380,8 @@ static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg)
pd->pos = -1;
pd->sr = 0;
- /* Enable all interrupts except wait */
- iowrite8(ioread8(ICIC(pd)) | ICIC_ALE | ICIC_TACKE | ICIC_DTEE,
- ICIC(pd));
+ /* Enable all interrupts to begin with */
+ iowrite8(ICIC_WAITE | ICIC_ALE | ICIC_TACKE | ICIC_DTEE, ICIC(pd));
return 0;
}
@@ -268,25 +414,18 @@ static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter,
if (!k)
dev_err(pd->dev, "Transfer request timed out\n");
- retry_count = 10;
+ retry_count = 1000;
again:
val = ioread8(ICSR(pd));
dev_dbg(pd->dev, "val 0x%02x pd->sr 0x%02x\n", val, pd->sr);
- if ((val | pd->sr) & (ICSR_TACK | ICSR_AL)) {
- err = -EIO;
- break;
- }
-
/* the interrupt handler may wake us up before the
* transfer is finished, so poll the hardware
* until we're done.
*/
-
- if (!(!(val & ICSR_BUSY) && (val & ICSR_SCLM) &&
- (val & ICSR_SDAM))) {
- msleep(1);
+ if (val & ICSR_BUSY) {
+ udelay(10);
if (retry_count--)
goto again;
@@ -294,6 +433,12 @@ again:
dev_err(pd->dev, "Polling timed out\n");
break;
}
+
+ /* handle missing acknowledge and arbitration lost */
+ if ((val | pd->sr) & (ICSR_TACK | ICSR_AL)) {
+ err = -EIO;
+ break;
+ }
}
deactivate_ch(pd);
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-27 04:40:06 +0000