Hi Greg,

the patch below has meanwhile been reverted by Wolfram Sang [1], because it has been superseded. Although the patch itself is not wrong, you also may want to revert it in order to avoid conflicts with the next version.

Best regards Christian

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...

On Sunday, 11 October 2020, 10:48:33 CEST, gregkh@linuxfoundation.org wrote:

This is a note to let you know that I've just added the patch titled

i2c: imx: Fix reset of I2SR_IAL flag

to the 5.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su... mary

The filename of the patch is: i2c-imx-fix-reset-of-i2sr_ial-flag.patch and it can be found in the queue-5.8 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From fa4d30556883f2eaab425b88ba9904865a4d00f3 Mon Sep 17 00:00:00 2001 From: Christian Eggers ceggers@arri.de Date: Wed, 7 Oct 2020 10:45:22 +0200 Subject: i2c: imx: Fix reset of I2SR_IAL flag MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit

From: Christian Eggers ceggers@arri.de

commit fa4d30556883f2eaab425b88ba9904865a4d00f3 upstream.

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 Cc: stable@vger.kernel.org Signed-off-by: Wolfram Sang wsa@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

---

drivers/i2c/busses/i2c-imx.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-)

--- 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_ 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_i

/* 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, 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; }

Patches currently in stable-queue which might be from ceggers@arri.de are

queue-5.8/i2c-imx-fix-reset-of-i2sr_ial-flag.patch