From 0af141327c877e9d9f6d0830ec9833229bfcfc37 Mon Sep 17 00:00:00 2001 From: Biwen Li Date: Thu, 24 Oct 2019 13:14:44 +0800 Subject: [PATCH] i2c: imx: correct code of errata A-010650 for layerscape platform - Simplify code with helper function i2c_imx_clr_al_bit - Fix an error about clearing arbitration lost bit - Fix an error that not set I2Cx_IBCR following by the workaround of A-010650 (in step 5) Reviewed-by: Clark Wang Signed-off-by: Biwen Li --- drivers/i2c/busses/i2c-imx.c | 38 ++++++++++++++++++------------------ 1 file changed, 19 insertions(+), 19 deletions(-) diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index 2a0599a4b558..40111a38970d 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -503,6 +503,14 @@ static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx) dma->chan_using = NULL; } +/* Clear arbitration lost bit */ +static void i2c_imx_clr_al_bit(unsigned int status, struct imx_i2c_struct *i2c_imx) +{ + status &= ~I2SR_IAL; + status |= (i2c_imx->hwdata->i2sr_clr_opcode & I2SR_IAL); + imx_i2c_write_reg(status, i2c_imx, IMX_I2C_I2SR); +} + static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy) { unsigned long orig_jiffies = jiffies; @@ -515,8 +523,7 @@ static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy) /* check for arbitration lost */ if (temp & I2SR_IAL) { - temp &= ~I2SR_IAL; - imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR); + i2c_imx_clr_al_bit(temp, i2c_imx); return -EAGAIN; } @@ -700,14 +707,6 @@ static void i2c_imx_clr_if_bit(unsigned int status, struct imx_i2c_struct *i2c_i imx_i2c_write_reg(status, i2c_imx, IMX_I2C_I2SR); } -/* Clear arbitration lost bit */ -static void i2c_imx_clr_al_bit(unsigned int status, struct imx_i2c_struct *i2c_imx) -{ - status &= ~I2SR_IAL; - status |= (i2c_imx->hwdata->i2sr_clr_opcode & I2SR_IAL); - imx_i2c_write_reg(status, i2c_imx, IMX_I2C_I2SR); -} - static irqreturn_t i2c_imx_master_isr(struct imx_i2c_struct *i2c_imx) { unsigned int status; @@ -1050,12 +1049,14 @@ static int i2c_imx_recovery_for_layerscape(struct imx_i2c_struct *i2c_imx) gpio_set_value(i2c_imx->gpio, 1); /* - * Set I2Cx_IBCR = 0h00 to generate a STOP and then - * set I2Cx_IBCR = 0h80 to reset + * Set I2Cx_IBCR = 0h00 to generate a STOP */ - temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); - temp &= ~(I2CR_MSTA | I2CR_MTX); - imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode, i2c_imx, IMX_I2C_I2CR); + + /* + * Set I2Cx_IBCR = 0h80 to reset the I2Cx controller + */ + imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode | I2CR_IEN, i2c_imx, IMX_I2C_I2CR); /* Restore the saved value of the register SCFG_RCWPMUXCR0 */ if (i2c_imx->need_set_pmuxcr == 1) { @@ -1069,10 +1070,9 @@ static int i2c_imx_recovery_for_layerscape(struct imx_i2c_struct *i2c_imx) * I2C_IBSR[IBAL] = 1 */ temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); - if (temp & I2SR_IAL) { - temp &= ~I2SR_IAL; - imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR); - } + if (temp & I2SR_IAL) + i2c_imx_clr_al_bit(temp, i2c_imx); + return 0; }