On Fri, Oct 09, 2020 at 09:11:32AM +0200, Oleksij Rempel wrote:
> Hi Christian,
>
> On Wed, Oct 07, 2020 at 10:45:22AM +0200, Christian Eggers wrote:
> > 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@xxxxxxx>
> > Fixes: 4b775022f6fd ("i2c: imx: add struct to hold more configurable quirks")
> > Reviewed-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
> > Cc: stable@xxxxxxxxxxxxxxx
> > ---
> > drivers/i2c/busses/i2c-imx.c | 20 +++++++++++++++-----
> > 1 file changed, 15 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
> > index 0ab5381aa012..cbdcab73a055 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 W1C and Vybrid uses W0C.
> > + */
>
> This comment need correction. The 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;
> > }
> >
> > @@ -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;
> > }
> > --
>
> Otherwise
>
> Acked-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
By reviewing the second patch we found at least one more missing Vybrid
related case in the i2c_imx_trx_complete() function:
imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR);
this is OK for iMX by broken on Vybrid.
Since you already fixing it in this patch for some of IMX_I2C_I2SR
writes, please do it here as well. This is the last unhandled case...:)
Regards,
Oleksij
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