diff options
author | Wolfram Sang <wsa+renesas@sang-engineering.com> | 2019-04-03 14:40:13 +0200 |
---|---|---|
committer | Wolfram Sang <wsa@the-dreams.de> | 2019-04-16 13:08:13 +0200 |
commit | 89f845a6dcd38a2b83b995cb6a8c7ef3e5abfd3a (patch) | |
tree | 7021d32250c116a783736d7bbce490ae81326c47 /drivers | |
parent | 77c1e1e062b639c98ce093f607637ac027936d04 (diff) |
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>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/i2c/busses/i2c-omap.c | 76 |
1 files changed, 63 insertions, 13 deletions
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index cd9c65f3d404..faa0394048a0 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -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, }; |