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authorChristian Eggers2020-10-09 13:03:18 +0200
committerWolfram Sang2020-12-02 21:28:19 +0100
commit384a9565f70a876c2e78e58c5ca0bbf0547e4f6d (patch)
tree0796bc6400fd14c3cfb915f4b7698caa03a08653 /drivers
parent14718b3e129b058cb716a60c6faf40ef68661c54 (diff)
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: 4b775022f6fd ("i2c: imx: add struct to hold more configurable quirks") Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Oleksij Rempel <o.rempel@pengutronix.de> Cc: stable@vger.kernel.org Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/i2c/busses/i2c-imx.c22
1 files changed, 16 insertions, 6 deletions
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index c98529c76348..39e98d216016 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -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 W0C and Vybrid uses W1C.
+ */
+ 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;
}
@@ -469,7 +481,7 @@ static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx, bool atomic)
*/
readb_poll_timeout_atomic(addr, regval, regval & I2SR_IIF, 5, 1000 + 100);
i2c_imx->i2csr = regval;
- imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR);
+ i2c_imx_clear_irq(i2c_imx, I2SR_IIF | I2SR_IAL);
} else {
wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10);
}
@@ -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;
}