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i2c: imx: Fix reset of I2SR_IAL flag 

According to the "VFxxx Controller Reference Manual" (and the comment
block starting at line 97), Vybrid requires writing a one for clearing
an interrupt flag. Syncing the method for clearing I2SR_IIF in
i2c_imx_isr().

Signed-off-by: Christian Eggers <ceggers@arri.de>
Fixes: 4b775022f6 ("i2c: imx: add struct to hold more configurable quirks")
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Wolfram Sang <wsa@kernel.org>
This commit is contained in:
Christian Eggers 2020-10-07 10:45:22 +02:00 committed by Wolfram Sang
parent 549738f15d
commit fa4d305568
1 changed files with 15 additions and 5 deletions
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20
drivers/i2c/busses/i2c-imx.c
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@ -412,6 +412,19 @@ static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx)
dma->chan_using = NULL;
}
static void i2c_imx_clear_irq(struct imx_i2c_struct *i2c_imx, unsigned int bits)
{
unsigned int temp;
/*
* i2sr_clr_opcode is the value to clear all interrupts. Here we want to
* clear only <bits>, so we write ~i2sr_clr_opcode with just <bits>
* toggled. This is required because i.MX needs W1C and Vybrid uses W0C.
*/
temp = ~i2c_imx->hwdata->i2sr_clr_opcode ^ bits;
imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
}
static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool atomic)
{
unsigned long orig_jiffies = jiffies;
@ -424,8 +437,7 @@ static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool a
/* check for arbitration lost */
if (temp & I2SR_IAL) {
temp &= ~I2SR_IAL;
imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
return -EAGAIN;
}
@ -623,9 +635,7 @@ static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
if (temp & I2SR_IIF) {
/* save status register */
i2c_imx->i2csr = temp;
temp &= ~I2SR_IIF;
temp |= (i2c_imx->hwdata->i2sr_clr_opcode & I2SR_IIF);
imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
i2c_imx_clear_irq(i2c_imx, I2SR_IIF);
wake_up(&i2c_imx->queue);
return IRQ_HANDLED;
}