static void omap_i2c_idle(struct omap_i2c_dev *dev)
{
struct platform_device *pdev;
struct omap_i2c_bus_platform_data *pdata;
u16 iv;
WARN_ON(dev->idle);
pdev = to_platform_device(dev->dev);
pdata = pdev->dev.platform_data;
dev->iestate = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
if (dev->rev >= OMAP_I2C_REV_ON_4430)
omap_i2c_write_reg(dev, OMAP_I2C_IRQENABLE_CLR, 1);
else
omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0);
if (dev->rev < OMAP_I2C_REV_2) {
iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); /* Read clears */
} else {
omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, dev->iestate);
/* Flush posted write before the dev->idle store occurs */
omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
}
dev->idle = 1;
pm_runtime_put_sync(&pdev->dev);
}
static int omap_i2c_reset(struct omap_i2c_dev *dev)
{
unsigned long timeout;
u16 sysc;
if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
sysc = omap_i2c_read_reg(dev, OMAP_I2C_SYSC_REG);
/* Disable I2C controller before soft reset */
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
~(OMAP_I2C_CON_EN));
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
/* For some reason we need to set the EN bit before the
* reset done bit gets set. */
timeout = jiffies + OMAP_I2C_TIMEOUT;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
SYSS_RESETDONE_MASK)) {
if (time_after(jiffies, timeout)) {
dev_warn(dev->dev, "timeout waiting "
"for controller reset\n");
return -ETIMEDOUT;
}
msleep(1);
}
/* SYSC register is cleared by the reset; rewrite it */
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, sysc);
}
return 0;
}
static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat)
{
/*
* I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8)
* Not applicable for OMAP4.
* Under certain rare conditions, RDR could be set again
* when the bus is busy, then ignore the interrupt and
* clear the interrupt.
*/
if (stat & OMAP_I2C_STAT_RDR) {
/* Step 1: If RDR is set, clear it */
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
/* Step 2: */
if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
& OMAP_I2C_STAT_BB)) {
/* Step 3: */
if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
& OMAP_I2C_STAT_RDR) {
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
dev_dbg(dev->dev, "RDR when bus is busy.\n");
}
}
}
}
static irqreturn_t
omap_i2c_rev1_isr(int this_irq, void *dev_id)
{
struct omap_i2c_dev *dev = dev_id;
u16 iv, w;
if (dev->idle)
return IRQ_NONE;
iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
switch (iv) {
case 0x00: /* None */
break;
case 0x01: /* Arbitration lost */
dev_err(dev->dev, "Arbitration lost\n");
omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
break;
case 0x02: /* No acknowledgement */
omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
break;
case 0x03: /* Register access ready */
omap_i2c_complete_cmd(dev, 0);
break;
case 0x04: /* Receive data ready */
if (dev->buf_len) {
w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
*dev->buf++ = w;
dev->buf_len--;
if (dev->buf_len) {
*dev->buf++ = w >> 8;
dev->buf_len--;
}
} else
/*
* Wait while BB-bit doesn't reflect the I2C bus state
*
* In a multimaster environment, after IP software reset, BB-bit value doesn't
* correspond to the current bus state. It may happen what BB-bit will be 0,
* while the bus is busy due to another I2C master activity.
* Here are BB-bit values after reset:
* SDA SCL BB NOTES
* 0 0 0 1, 2
* 1 0 0 1, 2
* 0 1 1
* 1 1 0 3
* Later, if IP detect SDA=0 and SCL=1 (ACK) or SDA 1->0 while SCL=1 (START)
* combinations on the bus, it set BB-bit to 1.
* If IP detect SDA 0->1 while SCL=1 (STOP) combination on the bus,
* it set BB-bit to 0 and BF to 1.
* BB and BF bits correctly tracks the bus state while IP is suspended
* BB bit became valid on the next FCLK clock after CON_EN bit set
*
* NOTES:
* 1. Any transfer started when BB=0 and bus is busy wouldn't be
* completed by IP and results in controller timeout.
* 2. Any transfer started when BB=0 and SCL=0 results in IP
* starting to drive SDA low. In that case IP corrupt data
* on the bus.
* 3. Any transfer started in the middle of another master's transfer
* results in unpredictable results and data corruption
*/
static int omap_i2c_wait_for_bb_valid(struct omap_i2c_dev *dev)
{
unsigned long bus_free_timeout = 0;
unsigned long timeout;
int bus_free = 0;
u16 stat, systest;
if (dev->bb_valid)
return 0;
timeout = jiffies + OMAP_I2C_TIMEOUT;
while (1) {
stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
/*
* We will see BB or BF event in a case IP had detected any
* activity on the I2C bus. Now IP correctly tracks the bus
* state. BB-bit value is valid.
*/
if (stat & (OMAP_I2C_STAT_BB | OMAP_I2C_STAT_BF))
break;
/*
* Otherwise, we must look signals on the bus to make
* the right decision.
*/
systest = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG);
if ((systest & OMAP_I2C_SYSTEST_SCL_I_FUNC) &&
(systest & OMAP_I2C_SYSTEST_SDA_I_FUNC)) {
if (!bus_free) {
bus_free_timeout = jiffies +
OMAP_I2C_BUS_FREE_TIMEOUT;
bus_free = 1;
}
/*
* SDA and SCL lines was high for 10 ms without bus
* activity detected. The bus is free. Consider
* BB-bit value is valid.
*/
if (time_after(jiffies, bus_free_timeout))
break;
} else {
bus_free = 0;
}
if (time_after(jiffies, timeout)) {
dev_warn(dev->dev, "timeout waiting for bus ready\n");
return -ETIMEDOUT;
}
msleep(1);
}
dev->bb_valid = 1;
return 0;
}
static int omap_i2c_reset(struct omap_i2c_dev *dev)
{
unsigned long timeout;
/* TTX-897: Fix Wi-Fi on/off causes system mysteriously reboots
* TTX-3735: Battery capacity show 0% which against actual battery
* capacity while doing manual power on/off test
* TTX-2798: Device stuck on boot screen after factory reset loop
* or reboot loop test or flashing loop test
* The arch/arm/mach-omap2/i2c.c: omap_i2c_reset() function that
* this function used to call is not restoring the OMAP_I2C_SYSC_REG
* register after a soft reset of I2C module. As a result, the clocks
* for the I2C module were getting cut even after we call
* pm_runtime_get_sync().
* So, we explicity soft reset the I2C module ourselves and restore
* the SYSC register
*/
/* Disable I2C controller before soft reset */
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
~(OMAP_I2C_CON_EN));
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
/* According to TRM 23.1.4.3 HS I2C Software Reset we need to set
* the EN bit before the before we start checking on reset done
*/
timeout = jiffies + OMAP_I2C_TIMEOUT;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
SYSS_RESETDONE_MASK)) {
if (time_after(jiffies, timeout)) {
dev_warn(dev->dev, "timeout waiting "
"for controller reset\n");
return -ETIMEDOUT;
}
mdelay(1);
}
/* SYSC register is cleared by the reset; rewrite it */
if (dev->rev == OMAP_I2C_REV_ON_2430) {
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
SYSC_AUTOIDLE_MASK);
} else if (dev->rev >= OMAP_I2C_REV_ON_3430) {
dev->syscstate = SYSC_AUTOIDLE_MASK;
dev->syscstate |= SYSC_ENAWAKEUP_MASK;
dev->syscstate |= (SYSC_IDLEMODE_SMARTWKUP <<
__ffs(SYSC_SIDLEMODE_MASK));
dev->syscstate |= (SYSC_CLOCKACTIVITY_FCLK <<
__ffs(SYSC_CLOCKACTIVITY_MASK));
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
dev->syscstate);
}
return 0;
}
static void omap_i2c_idle(struct omap_i2c_dev *dev)
{
u16 iv;
dev->idle = 1;
dev->iestate = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0);
if (dev->rev1)
iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
else
omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, dev->iestate);
clk_disable(dev->fclk);
if (dev->iclk != NULL)
clk_disable(dev->iclk);
}
static int omap_i2c_dpll_notifier(struct notifier_block *nb,
unsigned long val, void *data)
{
struct omap_i2c_dev *dev = container_of(nb, struct omap_i2c_dev, nb);
struct clk_notifier_data *cnd = (struct clk_notifier_data *)data;
unsigned int count = 0;
spin_lock(&dev->dpll_lock);
if (val == CLK_POST_RATE_CHANGE &&
cnd->old_rate == OMAP_I2C_MASTER_CLOCK)
dev->dpll_entry = 1;
else if (val == CLK_PRE_RATE_CHANGE &&
cnd->old_rate == OMAP_I2C_DPLL_CLOCK) {
/*
* If the device is not idle in the DPLL exit
* wait for the bus to become free.
*/
if (0 == dev->idle) {
while (omap_i2c_read_reg(dev,
OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
if (count++ == 100) {
dev_warn(dev->dev,
"I2C is busy during DPLL cascading exit\n");
break;
}
}
}
dev->dpll_exit = 1;
}
spin_unlock(&dev->dpll_lock);
return 0;
}
/*
* Bus Clear
*/
static int omap_i2c_bus_clear(struct omap_i2c_dev *dev)
{
u16 w;
/* Per the I2C specification, if we are stuck in a bus busy state
* we can attempt a bus clear to try and recover the bus by sending
* at least 9 clock pulses on SCL. Put the I2C in a test mode so it
* will output a continuous clock on SCL.
*/
disable_irq(dev->irq);
w = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG);
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG,
(OMAP_I2C_SYSTEST_ST_EN | OMAP_I2C_SYSTEST_TMODE_TEST));
msleep(1);
omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, w);
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
omap_i2c_reset(dev);
omap_i2c_init(dev);
enable_irq(dev->irq);
return omap_i2c_wait_for_bb(dev);
}
static int omap_i2c_reset(struct omap_i2c_dev *dev)
{
unsigned long timeout;
if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
/* Disable I2C controller before soft reset */
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
~(OMAP_I2C_CON_EN));
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
/* For some reason we need to set the EN bit before the
* reset done bit gets set. */
timeout = jiffies + OMAP_I2C_TIMEOUT;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
SYSS_RESETDONE_MASK)) {
if (time_after(jiffies, timeout)) {
dev_warn(dev->dev, "timeout waiting "
"for controller reset\n");
return -ETIMEDOUT;
}
mdelay(1);
}
/* SYSC register is cleared by the reset; rewrite it */
if (dev->rev == OMAP_I2C_REV_ON_2430) {
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
SYSC_AUTOIDLE_MASK);
} else if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) {
dev->syscstate = SYSC_AUTOIDLE_MASK;
dev->syscstate |= SYSC_ENAWAKEUP_MASK;
dev->syscstate |= (SYSC_IDLEMODE_SMART <<
__ffs(SYSC_SIDLEMODE_MASK));
dev->syscstate |= (SYSC_CLOCKACTIVITY_FCLK <<
__ffs(SYSC_CLOCKACTIVITY_MASK));
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
dev->syscstate);
}
}
return 0;
}
static void omap_i2c_idle(struct omap_i2c_dev *dev)
{
u16 iv;
dev->iestate = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
if (dev->dtrev == OMAP_I2C_IP_VERSION_2)
omap_i2c_write_reg(dev, OMAP_I2C_IP_V2_IRQENABLE_CLR, 1);
else
omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0);
if (dev->rev < OMAP_I2C_OMAP1_REV_2) {
iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); /* Read clears */
} else {
omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, dev->iestate);
/* Flush posted write */
omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
}
}
static void omap_i2c_idle(struct omap_i2c_dev *dev)
{
u16 iv;
WARN_ON(dev->idle);
dev->iestate = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0);
if (dev->rev < OMAP_I2C_REV_2) {
iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); /* Read clears */
} else {
omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, dev->iestate);
/* Flush posted write before the dev->idle store occurs */
omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
}
dev->idle = 1;
clk_disable(dev->fclk);
clk_disable(dev->iclk);
}
static void omap_i2c_idle(struct omap_i2c_dev *dev)
{
struct omap_i2c_bus_platform_data *pdata;
u16 iv;
pdata = dev->dev->platform_data;
dev->iestate = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0);
if (dev->rev < OMAP_I2C_OMAP1_REV_2) {
iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); /* Read clears */
} else {
omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, dev->iestate);
/* Flush posted write */
omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
}
}
/*
* Prepare controller for a transaction and call omap_i2c_xfer_msg
* to do the work during IRQ processing.
*/
static int
omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
{
struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
int i;
int r;
//--[[ LGE_UBIQUIX_MODIFIED_START : [email protected] [2011.11.16] - In case a peripheral is holding the DATA bus low, reset the I2C controller
u16 val;
//--]] LGE_UBIQUIX_MODIFIED_END : [email protected] [2011.11.16]- In case a peripheral is holding the DATA bus low, reset the I2C controller
/*
* hwspinlock is used to time share the I2C module between A9 and Ducati
* on OMAP4. To avoid spurious IRQ due to I2C transaction initiated on
* Ducati sub system I2C IRQ is enabled and disabled on i2c transfers.
*/
omap_i2c_hwspinlock_lock(dev);
omap_i2c_unidle(dev);
enable_irq(dev->irq);
r = omap_i2c_wait_for_bb(dev);
//--[[ LGE_UBIQUIX_MODIFIED_START : [email protected] [2011.11.16] - In case a peripheral is holding the DATA bus low, reset the I2C controller
/* If timeout, try to again check after soft reset of I2C block */
if (WARN_ON(r == -ETIMEDOUT)) {
/* Provide a permanent clock to recover the peripheral */
val = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG);
val |= (OMAP_I2C_SYSTEST_ST_EN |
OMAP_I2C_SYSTEST_FREE |
(2 << OMAP_I2C_SYSTEST_TMODE_SHIFT));
omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, val);
msleep(1);
omap_i2c_init(dev);
r = omap_i2c_wait_for_bb(dev);
}
//--]] LGE_UBIQUIX_MODIFIED_END : [email protected] [2011.11.16]- In case a peripheral is holding the DATA bus low, reset the I2C controller
if (r < 0)
goto out;
for (i = 0; i < num; i++) {
r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
if (r != 0)
break;
}
if (r == 0)
r = num;
omap_i2c_wait_for_bb(dev);
out:
disable_irq_nosync(dev->irq);
omap_i2c_idle(dev);
omap_i2c_hwspinlock_unlock(dev);
return r;
}
/*
* Prepare controller for a transaction and call omap_i2c_xfer_msg
* to do the work during IRQ processing.
*/
static int
omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
{
struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
int i;
int r;
u16 val;
omap_i2c_unidle(dev);
r = omap_i2c_wait_for_bb(dev);
/* If timeout, try to again check after soft reset of I2C block */
if (WARN_ON(r == -ETIMEDOUT)) {
/* Provide a permanent clock to recover the peripheral */
val = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG);
val |= (OMAP_I2C_SYSTEST_ST_EN |
OMAP_I2C_SYSTEST_FREE |
(2 << OMAP_I2C_SYSTEST_TMODE_SHIFT));
omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, val);
msleep(1);
omap_i2c_init(dev);
r = omap_i2c_wait_for_bb(dev);
}
if (r < 0)
goto out;
/*
* When waiting for completion of a i2c transfer, we need to
* set a wake up latency constraint for the MPU. This is to
* ensure quick enough wakeup from idle, when transfer
* completes.
*/
if (dev->pm_qos)
pm_qos_update_request(dev->pm_qos, dev->latency);
for (i = 0; i < num; i++) {
r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
if (r != 0)
break;
}
if (dev->pm_qos)
pm_qos_update_request(dev->pm_qos, PM_QOS_DEFAULT_VALUE);
if (r == 0)
r = num;
omap_i2c_wait_for_bb(dev);
out:
omap_i2c_idle(dev);
return r;
}
/*
* Waiting on Bus Busy
*/
static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
{
unsigned long timeout;
timeout = jiffies + OMAP_I2C_TIMEOUT;
while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
if (time_after(jiffies, timeout))
return i2c_recover_bus(&dev->adapter);
msleep(1);
}
return 0;
}
static irqreturn_t
omap_i2c_rev1_isr(int this_irq, void *dev_id)
{
struct omap_i2c_dev *dev = dev_id;
u16 iv, w;
if (dev->idle)
return IRQ_NONE;
iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
switch (iv) {
case 0x00: /* None */
break;
/* <-- [email protected] delete arbitration mechanism for solving mg touch suspend/resume issue*/
#if 0
case 0x01: /* Arbitration lost */
dev_err(dev->dev, "Arbitration lost\n");
omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
break;
#endif
/* [email protected] delete arbitration mechanism for solving mg touch suspend/resume issue -->*/
case 0x02: /* No acknowledgement */
omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
break;
case 0x03: /* Register access ready */
omap_i2c_complete_cmd(dev, 0);
break;
case 0x04: /* Receive data ready */
if (dev->buf_len) {
w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
*dev->buf++ = w;
dev->buf_len--;
if (dev->buf_len) {
*dev->buf++ = w >> 8;
dev->buf_len--;
}
} else
static int omap_i2c_unidle(struct omap_i2c_dev *dev)
{
struct platform_device *pdev;
struct omap_i2c_bus_platform_data *pdata;
int ret = 0;
WARN_ON(!dev->idle);
pdev = to_platform_device(dev->dev);
pdata = pdev->dev.platform_data;
ret = pm_runtime_get_sync(&pdev->dev);
if (IS_ERR_VALUE(ret)) {
dev_err(&pdev->dev,"%s: failed to get sync\n", __func__);
return ret;
}
if (cpu_is_omap34xx() || cpu_is_omap44xx()) {
unsigned long delay;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, dev->bufstate);
omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
delay = jiffies + OMAP_I2C_TIMEOUT;
while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG)
& OMAP_I2C_SYSS_RDONE)) {
if (time_after(jiffies, delay)) {
dev_err(dev->dev, "omap i2c unidle timeout\n");
return -ETIMEDOUT;
}
cpu_relax();
}
}
dev->idle = 0;
if (cpu_is_omap44xx() && dev->rev >= OMAP_I2C_REV_ON_4430) {
omap_i2c_write_reg(dev, OMAP_I2C_IRQENABLE_CLR,0x6FFF);
omap_i2c_write_reg(dev, OMAP_I2C_IRQENABLE_SET, dev->iestate);
} else {
omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
}
return ret;
}
/*
* Waiting on Bus Busy
*/
static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
{
unsigned long timeout = 0;
while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
if (timeout > OMAP_I2C_TIMEOUT) {
dev_warn(dev->dev, "timeout waiting for bus ready\n");
omap_i2c_dump(dev);
return -ETIMEDOUT;
}
timeout += usleep_range(1000, 2000);
}
return 0;
}
/*
* Waiting on Bus Busy
*/
static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
{
unsigned long timeout;
timeout = jiffies + OMAP_I2C_TIMEOUT;
while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
if (time_after(jiffies, timeout)) {
dev_warn(dev->dev, "timeout waiting for bus ready\n");
return -ETIMEDOUT;
}
msleep(1);
}
return 0;
}
/*
* Prepare controller for a transaction and call omap_i2c_xfer_msg
* to do the work during IRQ processing.
*/
static int
omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
{
struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
int i;
int r;
u16 val;
omap_i2c_unidle(dev);
r = omap_i2c_wait_for_bb(dev);
schedule_timeout_uninterruptible(5);// DCY - this seems to prevent lockup with Multi-Master system
/* If timeout, try to again check after soft reset of I2C block */
if (WARN_ON(r == -ETIMEDOUT)) {
/* Provide a permanent clock to recover the peripheral */
val = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG);
val |= (OMAP_I2C_SYSTEST_ST_EN |
OMAP_I2C_SYSTEST_FREE |
(2 << OMAP_I2C_SYSTEST_TMODE_SHIFT));
omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, val);
msleep(1);
omap_i2c_init(dev);
r = omap_i2c_wait_for_bb(dev);
}
if (r < 0)
goto out;
for (i = 0; i < num; i++) {
r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
if (r != 0)
break;
}
if (r == 0)
r = num;
omap_i2c_wait_for_bb(dev);
out:
omap_i2c_idle(dev);
return r;
}
static void omap_i2c_resize_fifo(struct omap_i2c_dev *dev, u8 size, bool is_rx)
{
u16 buf;
if (dev->flags & OMAP_I2C_FLAG_NO_FIFO)
return;
/*
* Set up notification threshold based on message size. We're doing
* this to try and avoid draining feature as much as possible. Whenever
* we have big messages to transfer (bigger than our total fifo size)
* then we might use draining feature to transfer the remaining bytes.
*/
dev->threshold = clamp(size, (u8) 1, dev->fifo_size);
buf = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
if (is_rx) {
/* Clear RX Threshold */
buf &= ~(0x3f << 8);
buf |= ((dev->threshold - 1) << 8) | OMAP_I2C_BUF_RXFIF_CLR;
} else {
/* Clear TX Threshold */
buf &= ~0x3f;
buf |= (dev->threshold - 1) | OMAP_I2C_BUF_TXFIF_CLR;
}
omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
if (dev->rev < OMAP_I2C_REV_ON_3630)
dev->b_hw = 1; /* Enable hardware fixes */
/* calculate wakeup latency constraint for MPU */
if (dev->set_mpu_wkup_lat != NULL)
dev->latency = (1000000 * dev->threshold) /
(1000 * dev->speed / 8);
}
static void omap_i2c_idle(struct omap_i2c_dev *dev)
{
struct platform_device *pdev;
struct omap_i2c_bus_platform_data *pdata;
u16 iv;
WARN_ON(dev->idle);
pdev = to_platform_device(dev->dev);
pdata = pdev->dev.platform_data;
if (cpu_is_omap44xx() && dev->rev >= OMAP_I2C_REV_ON_4430)
omap_i2c_write_reg(dev, OMAP_I2C_IRQENABLE_CLR, 0x6FFF);
else
omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0);
if (dev->rev < OMAP_I2C_REV_2) {
iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); /* Read clears */
}
dev->idle = 1;
pm_runtime_put_sync(&pdev->dev);
}
static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
struct i2c_msg *msg, int stop)
{
struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
int r;
u16 w;
struct pm_qos_request_list *qos_handle = NULL;
dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
msg->addr, msg->len, msg->flags, stop);
if (msg->len == 0)
return -EINVAL;
omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
/* REVISIT: Could the STB bit of I2C_CON be used with probing? */
dev->buf = msg->buf;
dev->buf_len = msg->len;
omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
/* Clear the FIFO Buffers */
w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
init_completion(&dev->cmd_complete);
dev->cmd_err = 0;
w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
/* High speed configuration */
if (dev->speed > 400)
w |= OMAP_I2C_CON_OPMODE_HS;
if (msg->flags & I2C_M_TEN)
w |= OMAP_I2C_CON_XA;
if (!(msg->flags & I2C_M_RD))
w |= OMAP_I2C_CON_TRX;
if (!dev->b_hw && stop)
w |= OMAP_I2C_CON_STP;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
/*
* Don't write stt and stp together on some hardware.
*/
if (dev->b_hw && stop) {
unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
while (con & OMAP_I2C_CON_STT) {
con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
/* Let the user know if i2c is in a bad state */
if (time_after(jiffies, delay)) {
dev_err(dev->dev, "controller timed out "
"waiting for start condition to finish\n");
return -ETIMEDOUT;
}
cpu_relax();
}
w |= OMAP_I2C_CON_STP;
w &= ~OMAP_I2C_CON_STT;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
}
/*
* REVISIT: We should abort the transfer on signals, but the bus goes
* into arbitration and we're currently unable to recover from it.
*/
if (dev->set_mpu_wkup_lat != NULL)
dev->set_mpu_wkup_lat(&qos_handle, dev->latency);
r = wait_for_completion_timeout(&dev->cmd_complete,
OMAP_I2C_TIMEOUT);
if (dev->set_mpu_wkup_lat != NULL)
dev->set_mpu_wkup_lat(&qos_handle, -1);
dev->buf_len = 0;
if (r < 0)
return r;
/* <-- [email protected] add kernel restart function in case of i2c bus failure*/
if (r == 0) {
dev_err(dev->dev, "controller timed out\n");
omap_i2c_init(dev);
if (strcmp(dev_name(dev->dev), "i2c_omap.1") == 0)
i2c1_fail_counter++;
if (strcmp(dev_name(dev->dev), "i2c_omap.2") == 0)
i2c2_fail_counter++;
if ((i2c1_fail_counter > 0x20) || (i2c2_fail_counter > 0x20))
{
i2c1_fail_counter=0;
i2c2_fail_counter=0;
error_kernel_restart();
}
return -ETIMEDOUT;
}
else
{
if (strcmp(dev_name(dev->dev), "i2c_omap.1") == 0)
i2c1_fail_counter=0;
if (strcmp(dev_name(dev->dev), "i2c_omap.2") == 0)
i2c2_fail_counter=0;
}
/* [email protected] add kernel restart function in case of i2c bus failure -->*/
if (likely(!dev->cmd_err))
return 0;
/* We have an error */
/* <-- [email protected] delete arbitration mechanism for solving mg touch suspend/resume issue*/
#if 0
if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
OMAP_I2C_STAT_XUDF)) {
#else
if (dev->cmd_err & ( OMAP_I2C_STAT_ROVR |
OMAP_I2C_STAT_XUDF)) {
#endif
/* [email protected] delete arbitration mechanism for solving mg touch suspend/resume issue -->*/
omap_i2c_init(dev);
return -EAGAIN;
}
if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
if (msg->flags & I2C_M_IGNORE_NAK)
return 0;
if (stop) {
w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
w |= OMAP_I2C_CON_STP;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
}
return -EREMOTEIO;
}
return -EIO;
}
static void
omap_i2c_dpll_configure(struct omap_i2c_dev *dev,
struct omap_i2c_bus_platform_data *pdata,
unsigned long fclk_rate) {
unsigned long internal_clk;
u16 psc = 0, scll = 0, sclh = 0;
u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
if ((pdata->features & I2C_HAS_FASTMODE_PLUS)
&& dev->speed > 1000)
internal_clk = 96000;
else if (dev->speed > 400)
internal_clk = 19200;
else if (dev->speed > 100)
internal_clk = 9600;
else
internal_clk = 4000;
psc = fclk_rate / internal_clk;
psc = psc - 1;
if (dev->speed > 400) {
unsigned long scl;
/* For first phase of HS mode */
scl = internal_clk / 400;
fsscll = scl - (scl / 3) - 7;
fssclh = (scl / 3) - 5;
/* For second phase of HS mode */
scl = fclk_rate / dev->speed;
hsscll = scl - (scl / 3) - 7;
hssclh = (scl / 3) - 5;
} else if (dev->speed > 100) {
unsigned long scl;
/* Fast mode */
scl = internal_clk / dev->speed;
fsscll = scl - (scl / 3) - 7;
fssclh = (scl / 3) - 5;
} else {
/* Standard mode */
fsscll = internal_clk / (dev->speed * 2) - 7;
fssclh = internal_clk / (dev->speed * 2) - 5;
}
scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll;
sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh;
dev->pscstate = psc;
dev->scllstate = scll;
dev->sclhstate = sclh;
}
static int omap_i2c_init(struct omap_i2c_dev *dev)
{
u16 psc = 0;
unsigned long fclk_rate = 12000000;
unsigned long timeout;
if (!dev->rev1) {
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, OMAP_I2C_SYSC_SRST);
/* For some reason we need to set the EN bit before the
* reset done bit gets set. */
timeout = jiffies + OMAP_I2C_TIMEOUT;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
OMAP_I2C_SYSS_RDONE)) {
if (time_after(jiffies, timeout)) {
dev_warn(dev->dev, "timeout waiting "
"for controller reset\n");
return -ETIMEDOUT;
}
msleep(1);
}
}
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
if (cpu_class_is_omap1()) {
struct clk *armxor_ck;
armxor_ck = clk_get(NULL, "armxor_ck");
if (IS_ERR(armxor_ck))
dev_warn(dev->dev, "Could not get armxor_ck\n");
else {
fclk_rate = clk_get_rate(armxor_ck);
clk_put(armxor_ck);
}
/* TRM for 5912 says the I2C clock must be prescaled to be
* between 7 - 12 MHz. The XOR input clock is typically
* 12, 13 or 19.2 MHz. So we should have code that produces:
*
* XOR MHz Divider Prescaler
* 12 1 0
* 13 2 1
* 19.2 2 1
*/
if (fclk_rate > 12000000)
psc = fclk_rate / 12000000;
}
/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
/* Program desired operating rate */
fclk_rate /= (psc + 1) * 1000;
if (psc > 2)
psc = 2;
omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG,
fclk_rate / (clock * 2) - 7 + psc);
omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG,
fclk_rate / (clock * 2) - 7 + psc);
/* Take the I2C module out of reset: */
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
/* Enable interrupts */
omap_i2c_write_reg(dev, OMAP_I2C_IE_REG,
(OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
OMAP_I2C_IE_AL));
return 0;
}
/*
* Low level master read/write transaction.
*/
static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
struct i2c_msg *msg, int stop)
{
struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
int r;
u16 w;
dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
msg->addr, msg->len, msg->flags, stop);
if (msg->len == 0)
return -EINVAL;
omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
/* REVISIT: Could the STB bit of I2C_CON be used with probing? */
dev->buf = msg->buf;
dev->buf_len = msg->len;
omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
/* Clear the FIFO Buffers */
w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
init_completion(&dev->cmd_complete);
dev->cmd_err = 0;
w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
/* High speed configuration */
if (dev->speed > 400)
w |= OMAP_I2C_CON_OPMODE_HS;
if (msg->flags & I2C_M_TEN)
w |= OMAP_I2C_CON_XA;
if (!(msg->flags & I2C_M_RD))
w |= OMAP_I2C_CON_TRX;
if (!dev->b_hw && stop)
w |= OMAP_I2C_CON_STP;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
/*
* Don't write stt and stp together on some hardware.
*/
if (dev->b_hw && stop) {
unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
while (con & OMAP_I2C_CON_STT) {
con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
/* Let the user know if i2c is in a bad state */
if (time_after(jiffies, delay)) {
dev_err(dev->dev, "controller timed out "
"waiting for start condition to finish\n");
return -ETIMEDOUT;
}
cpu_relax();
}
w |= OMAP_I2C_CON_STP;
w &= ~OMAP_I2C_CON_STT;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
}
/*
* REVISIT: We should abort the transfer on signals, but the bus goes
* into arbitration and we're currently unable to recover from it.
*/
r = wait_for_completion_timeout(&dev->cmd_complete,
OMAP_I2C_TIMEOUT);
dev->buf_len = 0;
if (r < 0)
return r;
if (r == 0) {
dev_err(dev->dev, "controller timed out\n");
omap_i2c_init(dev);
return -ETIMEDOUT;
}
if (likely(!dev->cmd_err))
return 0;
/* We have an error */
if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
OMAP_I2C_STAT_XUDF)) {
omap_i2c_init(dev);
return -EIO;
}
if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
if (msg->flags & I2C_M_IGNORE_NAK)
return 0;
if (stop) {
w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
w |= OMAP_I2C_CON_STP;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
}
return -EREMOTEIO;
}
return -EIO;
}
static void omap_i2c_dump(struct omap_i2c_dev *dev)
{
struct clk *fclk;
unsigned long fclk_rate;
dev_info(dev->dev, "sysc=0x%04x stat=0x%04x syss=0x%04x con=0x%04x\n",
omap_i2c_read_reg(dev, OMAP_I2C_SYSC_REG),
omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG),
omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG),
omap_i2c_read_reg(dev, OMAP_I2C_CON_REG));
pr_info("we=0x%04x sa=0x%04x cnt=%d buf=0x%04x bufstat=0x%04x\n",
omap_i2c_read_reg(dev, OMAP_I2C_WE_REG),
omap_i2c_read_reg(dev, OMAP_I2C_SA_REG),
omap_i2c_read_reg(dev, OMAP_I2C_CNT_REG),
omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG),
omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG));
fclk = clk_get(dev->dev, "fck");
fclk_rate = clk_get_rate(fclk);
clk_put(fclk);
pr_info("fclk=%lu"
#ifdef CONFIG_ARCH_OMAP4
" gated=%s"
#endif
" psc=0x%04x scll=0x%04x sclh=0x%04x\n",
fclk_rate,
#ifdef CONFIG_ARCH_OMAP4
__raw_readl(OMAP4430_CM_L4PER_CLKSTCTRL) &
OMAP4430_CLKACTIVITY_PER_96M_GFCLK_MASK ? "no" : "yes",
#endif
omap_i2c_read_reg(dev, OMAP_I2C_PSC_REG),
omap_i2c_read_reg(dev, OMAP_I2C_SCLL_REG),
omap_i2c_read_reg(dev, OMAP_I2C_SCLH_REG));
#ifdef CONFIG_ARCH_OMAP4
pr_info("CLKCTRL: 1:0x%08x 2:0x%08x 3:0x%08x 4:0x%08x\n",
__raw_readl(OMAP4430_CM_L4PER_I2C1_CLKCTRL),
__raw_readl(OMAP4430_CM_L4PER_I2C2_CLKCTRL),
__raw_readl(OMAP4430_CM_L4PER_I2C3_CLKCTRL),
__raw_readl(OMAP4430_CM_L4PER_I2C4_CLKCTRL));
#endif
}
static int omap_i2c_init(struct omap_i2c_dev *dev)
{
u16 psc = 0, scll = 0, sclh = 0, buf = 0;
u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
unsigned long fclk_rate = 12000000;
unsigned long timeout;
unsigned long internal_clk = 0;
struct clk *fclk;
if (dev->rev >= OMAP_I2C_REV_2) {
/* Disable I2C controller before soft reset */
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
~(OMAP_I2C_CON_EN));
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
/* For some reason we need to set the EN bit before the
* reset done bit gets set. */
timeout = jiffies + OMAP_I2C_TIMEOUT;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
SYSS_RESETDONE_MASK)) {
if (time_after(jiffies, timeout)) {
dev_warn(dev->dev, "timeout waiting "
"for controller reset\n");
return -ETIMEDOUT;
}
msleep(1);
}
/* SYSC register is cleared by the reset; rewrite it */
if (dev->rev == OMAP_I2C_REV_ON_2430) {
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
SYSC_AUTOIDLE_MASK);
} else if (dev->rev >= OMAP_I2C_REV_ON_3430) {
dev->syscstate = SYSC_AUTOIDLE_MASK;
dev->syscstate |= SYSC_ENAWAKEUP_MASK;
dev->syscstate |= (SYSC_IDLEMODE_SMART <<
__ffs(SYSC_SIDLEMODE_MASK));
dev->syscstate |= (SYSC_CLOCKACTIVITY_FCLK <<
__ffs(SYSC_CLOCKACTIVITY_MASK));
omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
dev->syscstate);
/*
* Enabling all wakup sources to stop I2C freezing on
* WFI instruction.
* REVISIT: Some wkup sources might not be needed.
*/
dev->westate = OMAP_I2C_WE_ALL;
omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
}
}
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
if (cpu_class_is_omap1()) {
/*
* The I2C functional clock is the armxor_ck, so there's
* no need to get "armxor_ck" separately. Now, if OMAP2420
* always returns 12MHz for the functional clock, we can
* do this bit unconditionally.
*/
fclk = clk_get(dev->dev, "fck");
fclk_rate = clk_get_rate(fclk);
clk_put(fclk);
/* TRM for 5912 says the I2C clock must be prescaled to be
* between 7 - 12 MHz. The XOR input clock is typically
* 12, 13 or 19.2 MHz. So we should have code that produces:
*
* XOR MHz Divider Prescaler
* 12 1 0
* 13 2 1
* 19.2 2 1
*/
if (fclk_rate > 12000000)
psc = fclk_rate / 12000000;
}
if (!(cpu_class_is_omap1() || cpu_is_omap2420())) {
/*
* HSI2C controller internal clk rate should be 19.2 Mhz for
* HS and for all modes on 2430. On 34xx we can use lower rate
* to get longer filter period for better noise suppression.
* The filter is iclk (fclk for HS) period.
*/
if (dev->speed > 400 || cpu_is_omap2430())
internal_clk = 19200;
else if (dev->speed > 100)
internal_clk = 9600;
else
internal_clk = 4000;
fclk = clk_get(dev->dev, "fck");
fclk_rate = clk_get_rate(fclk) / 1000;
clk_put(fclk);
/* Compute prescaler divisor */
psc = fclk_rate / internal_clk;
psc = psc - 1;
/* If configured for High Speed */
if (dev->speed > 400) {
unsigned long scl;
/* For first phase of HS mode */
scl = internal_clk / 400;
fsscll = scl - (scl / 3) - 7;
fssclh = (scl / 3) - 5;
/* For second phase of HS mode */
scl = fclk_rate / dev->speed;
hsscll = scl - (scl / 3) - 7;
hssclh = (scl / 3) - 5;
} else if (dev->speed > 100) {
unsigned long scl;
/* Fast mode */
scl = internal_clk / dev->speed;
fsscll = scl - (scl / 3) - 7;
fssclh = (scl / 3) - 5;
} else {
/* Standard mode */
fsscll = internal_clk / (dev->speed * 2) - 7;
fssclh = internal_clk / (dev->speed * 2) - 5;
}
scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll;
sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh;
} else {
/* Program desired operating rate */
fclk_rate /= (psc + 1) * 1000;
if (psc > 2)
psc = 2;
scll = fclk_rate / (dev->speed * 2) - 7 + psc;
sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
}
/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
/* SCL low and high time values */
omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
if (dev->fifo_size) {
/* Note: setup required fifo size - 1. RTRSH and XTRSH */
buf = (dev->fifo_size - 1) << 8 | OMAP_I2C_BUF_RXFIF_CLR |
(dev->fifo_size - 1) | OMAP_I2C_BUF_TXFIF_CLR;
omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
}
/* Take the I2C module out of reset: */
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
dev->errata = 0;
if (cpu_is_omap2430() || cpu_is_omap34xx())
dev->errata |= I2C_OMAP_ERRATA_I207;
/* Enable interrupts */
dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
OMAP_I2C_IE_AL) | ((dev->fifo_size) ?
(OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
if (cpu_is_omap34xx()) {
dev->pscstate = psc;
dev->scllstate = scll;
dev->sclhstate = sclh;
dev->bufstate = buf;
}
return 0;
}
/*
* Low level master read/write transaction.
*/
static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
struct i2c_msg *msg, int stop)
{
struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
#ifdef OMAP_HACK
u8 zero_byte = 0;
#endif
int r;
u16 w;
dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
msg->addr, msg->len, msg->flags, stop);
#ifndef OMAP_HACK
if (msg->len == 0)
return -EINVAL;
omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
/* REVISIT: Could the STB bit of I2C_CON be used with probing? */
dev->buf = msg->buf;
dev->buf_len = msg->len;
#else
omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
/* REVISIT: Remove this hack when we can get I2C chips from board-*.c
* files
* Sigh, seems we can't do zero length transactions. Thus, we
* can't probe for devices w/o actually sending/receiving at least
* a single byte. So we'll set count to 1 for the zero length
* transaction case and hope we don't cause grief for some
* arbitrary device due to random byte write/read during
* probes.
*/
if (msg->len == 0) {
dev->buf = &zero_byte;
dev->buf_len = 1;
} else {
dev->buf = msg->buf;
dev->buf_len = msg->len;
}
#endif
omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
/* Clear the FIFO Buffers */
w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
init_completion(&dev->cmd_complete);
dev->cmd_err = 0;
w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
/* High speed configuration */
if (dev->speed > 400)
w |= OMAP_I2C_CON_OPMODE_HS;
if (msg->flags & I2C_M_TEN)
w |= OMAP_I2C_CON_XA;
if (!(msg->flags & I2C_M_RD))
w |= OMAP_I2C_CON_TRX;
if (!dev->b_hw && stop)
w |= OMAP_I2C_CON_STP;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
if (dev->b_hw && stop) {
/* H/w behavior: dont write stt and stp together.. */
while (omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) & OMAP_I2C_CON_STT) {
/* Dont do anything - this will come in a couple of loops at max*/
}
w |= OMAP_I2C_CON_STP;
w &= ~OMAP_I2C_CON_STT;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
}
r = wait_for_completion_timeout(&dev->cmd_complete,
OMAP_I2C_TIMEOUT);
dev->buf_len = 0;
if (r < 0)
return r;
if (r == 0) {
dev_err(dev->dev, "controller timed out\n");
omap_i2c_init(dev);
return -ETIMEDOUT;
}
if (likely(!dev->cmd_err))
return 0;
/* We have an error */
if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
OMAP_I2C_STAT_XUDF)) {
omap_i2c_init(dev);
return -EIO;
}
if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
if (msg->flags & I2C_M_IGNORE_NAK)
return 0;
if (stop) {
w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
w |= OMAP_I2C_CON_STP;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
}
return -EREMOTEIO;
}
return -EIO;
}
/*
* Low level master read/write transaction.
*/
static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
struct i2c_msg *msg, int stop)
{
struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
int r;
u16 w;
dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
msg->addr, msg->len, msg->flags, stop);
if (msg->len == 0)
return -EINVAL;
omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
/* REVISIT: Could the STB bit of I2C_CON be used with probing? */
dev->buf = msg->buf;
dev->buf_len = msg->len;
omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
init_completion(&dev->cmd_complete);
dev->cmd_err = 0;
w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
if (msg->flags & I2C_M_TEN)
w |= OMAP_I2C_CON_XA;
if (!(msg->flags & I2C_M_RD))
w |= OMAP_I2C_CON_TRX;
if (stop)
w |= OMAP_I2C_CON_STP;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
r = wait_for_completion_interruptible_timeout(&dev->cmd_complete,
OMAP_I2C_TIMEOUT);
dev->buf_len = 0;
if (r < 0)
return r;
if (r == 0) {
dev_err(dev->dev, "controller timed out\n");
omap_i2c_init(dev);
return -ETIMEDOUT;
}
if (likely(!dev->cmd_err))
return 0;
/* We have an error */
if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
OMAP_I2C_STAT_XUDF)) {
omap_i2c_init(dev);
return -EIO;
}
if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
if (msg->flags & I2C_M_IGNORE_NAK)
return 0;
if (stop) {
w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
w |= OMAP_I2C_CON_STP;
omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
}
return -EREMOTEIO;
}
return -EIO;
}
