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i2c: omap: Add the master_xfer_atomic hook 

Add the master_xfer_atomic hook to enable i2c transactions in irq
disabled contexts like the poweroff case.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Keerthy <j-keerthy@ti.com>
[wsa: simplified code a little: 'timeout = !ret']
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
hifive-unleashed-5.2
Wolfram Sang 2019-04-03 14:40:13 +02:00 committed by Wolfram Sang
parent 77c1e1e062
commit 89f845a6dc
1 changed files with 63 additions and 13 deletions
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76
drivers/i2c/busses/i2c-omap.c
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@ -269,6 +269,8 @@ static const u8 reg_map_ip_v2[] = {
[OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30,
};
static int omap_i2c_xfer_data(struct omap_i2c_dev *omap);
static inline void omap_i2c_write_reg(struct omap_i2c_dev *omap,
int reg, u16 val)
{
@ -648,15 +650,28 @@ static void omap_i2c_resize_fifo(struct omap_i2c_dev *omap, u8 size, bool is_rx)
(1000 * omap->speed / 8);
}
static void omap_i2c_wait(struct omap_i2c_dev *omap)
{
u16 stat;
u16 mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG);
int count = 0;
do {
stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG);
count++;
} while (!(stat & mask) && count < 5);
}
/*
* Low level master read/write transaction.
*/
static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
struct i2c_msg *msg, int stop)
struct i2c_msg *msg, int stop, bool polling)
{
struct omap_i2c_dev *omap = i2c_get_adapdata(adap);
unsigned long timeout;
u16 w;
int ret;
dev_dbg(omap->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
msg->addr, msg->len, msg->flags, stop);
@ -680,7 +695,8 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
omap_i2c_write_reg(omap, OMAP_I2C_BUF_REG, w);
reinit_completion(&omap->cmd_complete);
if (!polling)
reinit_completion(&omap->cmd_complete);
omap->cmd_err = 0;
w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
@ -732,8 +748,18 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
* REVISIT: We should abort the transfer on signals, but the bus goes
* into arbitration and we're currently unable to recover from it.
*/
timeout = wait_for_completion_timeout(&omap->cmd_complete,
OMAP_I2C_TIMEOUT);
if (!polling) {
timeout = wait_for_completion_timeout(&omap->cmd_complete,
OMAP_I2C_TIMEOUT);
} else {
do {
omap_i2c_wait(omap);
ret = omap_i2c_xfer_data(omap);
} while (ret == -EAGAIN);
timeout = !ret;
}
if (timeout == 0) {
dev_err(omap->dev, "controller timed out\n");
omap_i2c_reset(omap);
@ -772,7 +798,8 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
* to do the work during IRQ processing.
*/
static int
omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
omap_i2c_xfer_common(struct i2c_adapter *adap, struct i2c_msg msgs[], int num,
bool polling)
{
struct omap_i2c_dev *omap = i2c_get_adapdata(adap);
int i;
@ -794,7 +821,8 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
omap->set_mpu_wkup_lat(omap->dev, omap->latency);
for (i = 0; i < num; i++) {
r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)),
polling);
if (r != 0)
break;
}
@ -813,6 +841,18 @@ out:
return r;
}
static int
omap_i2c_xfer_irq(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
{
return omap_i2c_xfer_common(adap, msgs, num, false);
}
static int
omap_i2c_xfer_polling(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
{
return omap_i2c_xfer_common(adap, msgs, num, true);
}
static u32
omap_i2c_func(struct i2c_adapter *adap)
{
@ -1035,10 +1075,8 @@ omap_i2c_isr(int irq, void *dev_id)
return ret;
}
static irqreturn_t
omap_i2c_isr_thread(int this_irq, void *dev_id)
static int omap_i2c_xfer_data(struct omap_i2c_dev *omap)
{
struct omap_i2c_dev *omap = dev_id;
u16 bits;
u16 stat;
int err = 0, count = 0;
@ -1056,7 +1094,8 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
if (!stat) {
/* my work here is done */
goto out;
err = -EAGAIN;
break;
}
dev_dbg(omap->dev, "IRQ (ISR = 0x%04x)\n", stat);
@ -1165,14 +1204,25 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
}
} while (stat);
omap_i2c_complete_cmd(omap, err);
return err;
}
static irqreturn_t
omap_i2c_isr_thread(int this_irq, void *dev_id)
{
int ret;
struct omap_i2c_dev *omap = dev_id;
ret = omap_i2c_xfer_data(omap);
if (ret != -EAGAIN)
omap_i2c_complete_cmd(omap, ret);
out:
return IRQ_HANDLED;
}
static const struct i2c_algorithm omap_i2c_algo = {
.master_xfer = omap_i2c_xfer,
.master_xfer = omap_i2c_xfer_irq,
.master_xfer_atomic = omap_i2c_xfer_polling,
.functionality = omap_i2c_func,
};