4.9-stable patches

added patches:
	i2c-imx-check-for-i2sr_ial-after-every-byte.patch
	i2c-imx-fix-reset-of-i2sr_ial-flag.patch

diff --git a/queue-4.9/i2c-imx-check-for-i2sr_ial-after-every-byte.patch b/queue-4.9/i2c-imx-check-for-i2sr_ial-after-every-byte.patch
new file mode 100644 (file)
index 0000000..1e11bea
--- /dev/null
+++ b/queue-4.9/i2c-imx-check-for-i2sr_ial-after-every-byte.patch
@@ -0,0 +1,46 @@
+From 1de67a3dee7a279ebe4d892b359fe3696938ec15 Mon Sep 17 00:00:00 2001
+From: Christian Eggers <ceggers@arri.de>
+Date: Fri, 9 Oct 2020 13:03:19 +0200
+Subject: i2c: imx: Check for I2SR_IAL after every byte
+
+From: Christian Eggers <ceggers@arri.de>
+
+commit 1de67a3dee7a279ebe4d892b359fe3696938ec15 upstream.
+
+Arbitration Lost (IAL) can happen after every single byte transfer. If
+arbitration is lost, the I2C hardware will autonomously switch from
+master mode to slave. If a transfer is not aborted in this state,
+consecutive transfers will not be executed by the hardware and will
+timeout.
+
+Signed-off-by: Christian Eggers <ceggers@arri.de>
+Tested (not extensively) on Vybrid VF500 (Toradex VF50):
+Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
+Acked-by: Oleksij Rempel <o.rempel@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 |   10 ++++++++++
+ 1 file changed, 10 insertions(+)
+
+--- a/drivers/i2c/busses/i2c-imx.c
++++ b/drivers/i2c/busses/i2c-imx.c
+@@ -465,6 +465,16 @@ static int i2c_imx_trx_complete(struct i
+               dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__);
+               return -ETIMEDOUT;
+       }
++
++      /* check for arbitration lost */
++      if (i2c_imx->i2csr & I2SR_IAL) {
++              dev_dbg(&i2c_imx->adapter.dev, "<%s> Arbitration lost\n", __func__);
++              i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
++
++              i2c_imx->i2csr = 0;
++              return -EAGAIN;
++      }
++
+       dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__);
+       i2c_imx->i2csr = 0;
+       return 0;

diff --git a/queue-4.9/i2c-imx-fix-reset-of-i2sr_ial-flag.patch b/queue-4.9/i2c-imx-fix-reset-of-i2sr_ial-flag.patch
new file mode 100644 (file)
index 0000000..213901b
--- /dev/null
+++ b/queue-4.9/i2c-imx-fix-reset-of-i2sr_ial-flag.patch
@@ -0,0 +1,72 @@
+From 384a9565f70a876c2e78e58c5ca0bbf0547e4f6d Mon Sep 17 00:00:00 2001
+From: Christian Eggers <ceggers@arri.de>
+Date: Fri, 9 Oct 2020 13:03:18 +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 384a9565f70a876c2e78e58c5ca0bbf0547e4f6d 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>
+Acked-by: Oleksij Rempel <o.rempel@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
+@@ -413,6 +413,19 @@ 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 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)
+ {
+       unsigned long orig_jiffies = jiffies;
+@@ -425,8 +438,7 @@ 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;
+               }
+ 
+@@ -595,9 +607,7 @@ 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;
+       }

diff --git a/queue-4.9/series b/queue-4.9/series
index 12b57e55df9bd087ebbc1a20bb018bc22ede13aa..21f19cb27e3c6f4e7c571c6aadf2c9231af445d8 100644 (file)
--- a/queue-4.9/series
+++ b/queue-4.9/series
@@ -31,3 +31,5 @@ alsa-hda-generic-add-option-to-enforce-preferred_dacs-pairs.patch
 tty-fix-session-locking.patch
 ftrace-fix-updating-ftrace_fl_tramp.patch
 cifs-fix-potential-use-after-free-in-cifs_echo_request.patch
+i2c-imx-fix-reset-of-i2sr_ial-flag.patch
+i2c-imx-check-for-i2sr_ial-after-every-byte.patch