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Commit 1ae49a15 authored by Russell King's avatar Russell King Committed by Wolfram Sang
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i2c: pxa: re-arrange functions to flow better 

Re-arrange the PXA I2C code to avoid forward declarations, and keep
similar functionality (e.g. the non-IRQ mode support) together. This
improves code readability.
Signed-off-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: default avatarWolfram Sang <wsa@kernel.org>
parent 8de32da2
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Showing with 162 additions and 163 deletions
drivers/i2c/busses/i2c-pxa.c
View file @ 1ae49a15
......@@ -326,7 +326,6 @@ static void i2c_pxa_scream_blue_murder(struct pxa_i2c *i2c, const char *why)
#endif /* ifdef DEBUG / else */
static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret);
static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id);
static inline int i2c_pxa_is_slavemode(struct pxa_i2c *i2c)
{
......@@ -741,34 +740,6 @@ static inline void i2c_pxa_stop_message(struct pxa_i2c *i2c)
writel(icr, _ICR(i2c));
}
static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c)
{
/* make timeout the same as for interrupt based functions */
long timeout = 2 * DEF_TIMEOUT;
/*
* Wait for the bus to become free.
*/
while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
udelay(1000);
show_state(i2c);
}
if (timeout < 0) {
show_state(i2c);
dev_err(&i2c->adap.dev,
"i2c_pxa: timeout waiting for bus free\n");
return I2C_RETRY;
}
/*
* Set master mode.
*/
writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
return 0;
}
/*
* PXA I2C send master code
* 1. Load master code to IDBR and send it.
......@@ -797,140 +768,6 @@ static int i2c_pxa_send_mastercode(struct pxa_i2c *i2c)
return (timeout == 0) ? I2C_RETRY : 0;
}
static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c,
struct i2c_msg *msg, int num)
{
unsigned long timeout = 500000; /* 5 seconds */
int ret = 0;
ret = i2c_pxa_pio_set_master(i2c);
if (ret)
goto out;
i2c->msg = msg;
i2c->msg_num = num;
i2c->msg_idx = 0;
i2c->msg_ptr = 0;
i2c->irqlogidx = 0;
i2c_pxa_start_message(i2c);
while (i2c->msg_num > 0 && --timeout) {
i2c_pxa_handler(0, i2c);
udelay(10);
}
i2c_pxa_stop_message(i2c);
/*
* We place the return code in i2c->msg_idx.
*/
ret = i2c->msg_idx;
out:
if (timeout == 0) {
i2c_pxa_scream_blue_murder(i2c, "timeout");
ret = I2C_RETRY;
}
return ret;
}
/*
* We are protected by the adapter bus mutex.
*/
static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
{
long timeout;
int ret;
/*
* Wait for the bus to become free.
*/
ret = i2c_pxa_wait_bus_not_busy(i2c);
if (ret) {
dev_err(&i2c->adap.dev, "i2c_pxa: timeout waiting for bus free\n");
goto out;
}
/*
* Set master mode.
*/
ret = i2c_pxa_set_master(i2c);
if (ret) {
dev_err(&i2c->adap.dev, "i2c_pxa_set_master: error %d\n", ret);
goto out;
}
if (i2c->high_mode) {
ret = i2c_pxa_send_mastercode(i2c);
if (ret) {
dev_err(&i2c->adap.dev, "i2c_pxa_send_mastercode timeout\n");
goto out;
}
}
spin_lock_irq(&i2c->lock);
i2c->msg = msg;
i2c->msg_num = num;
i2c->msg_idx = 0;
i2c->msg_ptr = 0;
i2c->irqlogidx = 0;
i2c_pxa_start_message(i2c);
spin_unlock_irq(&i2c->lock);
/*
* The rest of the processing occurs in the interrupt handler.
*/
timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5);
i2c_pxa_stop_message(i2c);
/*
* We place the return code in i2c->msg_idx.
*/
ret = i2c->msg_idx;
if (!timeout && i2c->msg_num) {
i2c_pxa_scream_blue_murder(i2c, "timeout");
ret = I2C_RETRY;
}
out:
return ret;
}
static int i2c_pxa_pio_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_pio_xfer(i2c, msgs, num);
if (ret != I2C_RETRY)
goto out;
if (i2c_debug)
dev_dbg(&adap->dev, "Retrying transmission\n");
udelay(100);
}
i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
ret = -EREMOTEIO;
out:
i2c_pxa_set_slave(i2c, ret);
return ret;
}
/*
* i2c_pxa_master_complete - complete the message and wake up.
*/
......@@ -1137,6 +974,71 @@ static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id)
return IRQ_HANDLED;
}
/*
* We are protected by the adapter bus mutex.
*/
static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
{
long timeout;
int ret;
/*
* Wait for the bus to become free.
*/
ret = i2c_pxa_wait_bus_not_busy(i2c);
if (ret) {
dev_err(&i2c->adap.dev, "i2c_pxa: timeout waiting for bus free\n");
goto out;
}
/*
* Set master mode.
*/
ret = i2c_pxa_set_master(i2c);
if (ret) {
dev_err(&i2c->adap.dev, "i2c_pxa_set_master: error %d\n", ret);
goto out;
}
if (i2c->high_mode) {
ret = i2c_pxa_send_mastercode(i2c);
if (ret) {
dev_err(&i2c->adap.dev, "i2c_pxa_send_mastercode timeout\n");
goto out;
}
}
spin_lock_irq(&i2c->lock);
i2c->msg = msg;
i2c->msg_num = num;
i2c->msg_idx = 0;
i2c->msg_ptr = 0;
i2c->irqlogidx = 0;
i2c_pxa_start_message(i2c);
spin_unlock_irq(&i2c->lock);
/*
* The rest of the processing occurs in the interrupt handler.
*/
timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5);
i2c_pxa_stop_message(i2c);
/*
* We place the return code in i2c->msg_idx.
*/
ret = i2c->msg_idx;
if (!timeout && i2c->msg_num) {
i2c_pxa_scream_blue_murder(i2c, "timeout");
ret = I2C_RETRY;
}
out:
return ret;
}
static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
{
......@@ -1174,6 +1076,103 @@ static const struct i2c_algorithm i2c_pxa_algorithm = {
#endif
};
/* Non-interrupt mode support */
static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c)
{
/* make timeout the same as for interrupt based functions */
long timeout = 2 * DEF_TIMEOUT;
/*
* Wait for the bus to become free.
*/
while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
udelay(1000);
show_state(i2c);
}
if (timeout < 0) {
show_state(i2c);
dev_err(&i2c->adap.dev,
"i2c_pxa: timeout waiting for bus free\n");
return I2C_RETRY;
}
/*
* Set master mode.
*/
writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
return 0;
}
static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c,
struct i2c_msg *msg, int num)
{
unsigned long timeout = 500000; /* 5 seconds */
int ret = 0;
ret = i2c_pxa_pio_set_master(i2c);
if (ret)
goto out;
i2c->msg = msg;
i2c->msg_num = num;
i2c->msg_idx = 0;
i2c->msg_ptr = 0;
i2c->irqlogidx = 0;
i2c_pxa_start_message(i2c);
while (i2c->msg_num > 0 && --timeout) {
i2c_pxa_handler(0, i2c);
udelay(10);
}
i2c_pxa_stop_message(i2c);
/*
* We place the return code in i2c->msg_idx.
*/
ret = i2c->msg_idx;
out:
if (timeout == 0) {
i2c_pxa_scream_blue_murder(i2c, "timeout");
ret = I2C_RETRY;
}
return ret;
}
static int i2c_pxa_pio_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_pio_xfer(i2c, msgs, num);
if (ret != I2C_RETRY)
goto out;
if (i2c_debug)
dev_dbg(&adap->dev, "Retrying transmission\n");
udelay(100);
}
i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
ret = -EREMOTEIO;
out:
i2c_pxa_set_slave(i2c, ret);
return ret;
}
static const struct i2c_algorithm i2c_pxa_pio_algorithm = {
.master_xfer = i2c_pxa_pio_xfer,
.functionality = i2c_pxa_functionality,
......
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