From 971490c89251ae1a4a9e2a85911de5c217a4027c Mon Sep 17 00:00:00 2001 From: Ye Li Date: Sun, 8 Jul 2018 11:46:43 +0800 Subject: [PATCH] lpi2c: Add bus busy error handling When doing "i2c dev 4; i2c probe" with ENET daughter card connected on iMX8QXP MEK board, we met a i2c bus busy issue, that the BBF of lpi2c always show busy, but the master is idle, and stop is detected (SDF set). This patch addes a handling to re-init the lpi2c master for this case. Then the issue can be worked around. Signed-off-by: Ye Li Acked-by: Peng Fan Reviewed-by: Heiko Schocher --- drivers/i2c/imx_lpi2c.c | 53 +++++++++++++++++++++++++++++-------------------- 1 file changed, 32 insertions(+), 21 deletions(-) diff --git a/drivers/i2c/imx_lpi2c.c b/drivers/i2c/imx_lpi2c.c index 585787a..ff07ca3 100644 --- a/drivers/i2c/imx_lpi2c.c +++ b/drivers/i2c/imx_lpi2c.c @@ -18,6 +18,8 @@ #define LPI2C_NACK_TOUT_MS 1 #define LPI2C_TIMEOUT_MS 100 +static int bus_i2c_init(struct udevice *bus, int speed); + /* Weak linked function for overridden by some SoC power function */ int __weak init_i2c_power(unsigned i2c_num) { @@ -91,8 +93,9 @@ static int bus_i2c_wait_for_tx_ready(struct imx_lpi2c_reg *regs) return result; } -static int bus_i2c_send(struct imx_lpi2c_reg *regs, u8 *txbuf, int len) +static int bus_i2c_send(struct udevice *bus, u8 *txbuf, int len) { + struct imx_lpi2c_reg *regs = (struct imx_lpi2c_reg *)devfdt_get_addr(bus); lpi2c_status_t result = LPI2C_SUCESS; /* empty tx */ @@ -111,8 +114,9 @@ static int bus_i2c_send(struct imx_lpi2c_reg *regs, u8 *txbuf, int len) return result; } -static int bus_i2c_receive(struct imx_lpi2c_reg *regs, u8 *rxbuf, int len) +static int bus_i2c_receive(struct udevice *bus, u8 *rxbuf, int len) { + struct imx_lpi2c_reg *regs = (struct imx_lpi2c_reg *)devfdt_get_addr(bus); lpi2c_status_t result = LPI2C_SUCESS; u32 val; ulong start_time = get_timer(0); @@ -153,15 +157,24 @@ static int bus_i2c_receive(struct imx_lpi2c_reg *regs, u8 *rxbuf, int len) return result; } -static int bus_i2c_start(struct imx_lpi2c_reg *regs, u8 addr, u8 dir) +static int bus_i2c_start(struct udevice *bus, u8 addr, u8 dir) { lpi2c_status_t result; + struct imx_lpi2c_reg *regs = + (struct imx_lpi2c_reg *)devfdt_get_addr(bus); u32 val; result = imx_lpci2c_check_busy_bus(regs); if (result) { debug("i2c: start check busy bus: 0x%x\n", result); - return result; + + /* Try to init the lpi2c then check the bus busy again */ + bus_i2c_init(bus, 100000); + result = imx_lpci2c_check_busy_bus(regs); + if (result) { + printf("i2c: Error check busy bus: 0x%x\n", result); + return result; + } } /* clear all status flags */ writel(0x7f00, ®s->msr); @@ -181,9 +194,11 @@ static int bus_i2c_start(struct imx_lpi2c_reg *regs, u8 addr, u8 dir) return result; } -static int bus_i2c_stop(struct imx_lpi2c_reg *regs) +static int bus_i2c_stop(struct udevice *bus) { lpi2c_status_t result; + struct imx_lpi2c_reg *regs = + (struct imx_lpi2c_reg *)devfdt_get_addr(bus); u32 status; ulong start_time; @@ -217,28 +232,28 @@ static int bus_i2c_stop(struct imx_lpi2c_reg *regs) return result; } -static int bus_i2c_read(struct imx_lpi2c_reg *regs, u32 chip, u8 *buf, int len) +static int bus_i2c_read(struct udevice *bus, u32 chip, u8 *buf, int len) { lpi2c_status_t result; - result = bus_i2c_start(regs, chip, 1); + result = bus_i2c_start(bus, chip, 1); if (result) return result; - result = bus_i2c_receive(regs, buf, len); + result = bus_i2c_receive(bus, buf, len); if (result) return result; return result; } -static int bus_i2c_write(struct imx_lpi2c_reg *regs, u32 chip, u8 *buf, int len) +static int bus_i2c_write(struct udevice *bus, u32 chip, u8 *buf, int len) { lpi2c_status_t result; - result = bus_i2c_start(regs, chip, 0); + result = bus_i2c_start(bus, chip, 0); if (result) return result; - result = bus_i2c_send(regs, buf, len); + result = bus_i2c_send(bus, buf, len); if (result) return result; @@ -353,18 +368,16 @@ static int bus_i2c_init(struct udevice *bus, int speed) static int imx_lpi2c_probe_chip(struct udevice *bus, u32 chip, u32 chip_flags) { - struct imx_lpi2c_reg *regs; lpi2c_status_t result; - regs = (struct imx_lpi2c_reg *)devfdt_get_addr(bus); - result = bus_i2c_start(regs, chip, 0); + result = bus_i2c_start(bus, chip, 0); if (result) { - bus_i2c_stop(regs); + bus_i2c_stop(bus); bus_i2c_init(bus, 100000); return result; } - result = bus_i2c_stop(regs); + result = bus_i2c_stop(bus); if (result) bus_i2c_init(bus, 100000); @@ -373,16 +386,14 @@ static int imx_lpi2c_probe_chip(struct udevice *bus, u32 chip, static int imx_lpi2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs) { - struct imx_lpi2c_reg *regs; int ret = 0, ret_stop; - regs = (struct imx_lpi2c_reg *)devfdt_get_addr(bus); for (; nmsgs > 0; nmsgs--, msg++) { debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len); if (msg->flags & I2C_M_RD) - ret = bus_i2c_read(regs, msg->addr, msg->buf, msg->len); + ret = bus_i2c_read(bus, msg->addr, msg->buf, msg->len); else { - ret = bus_i2c_write(regs, msg->addr, msg->buf, + ret = bus_i2c_write(bus, msg->addr, msg->buf, msg->len); if (ret) break; @@ -392,7 +403,7 @@ static int imx_lpi2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs) if (ret) debug("i2c_write: error sending\n"); - ret_stop = bus_i2c_stop(regs); + ret_stop = bus_i2c_stop(bus); if (ret_stop) debug("i2c_xfer: stop bus error\n");