All of lore.kernel.org
 help / color / mirror / Atom feed
From: dillon.minfei@gmail.com
To: robh+dt@kernel.org, mcoquelin.stm32@gmail.com,
	alexandre.torgue@st.com, p.zabel@pengutronix.de,
	pierre-yves.mordret@st.com, philippe.schenker@toradex.com
Cc: linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-stm32@st-md-mailman.stormreply.com,
	linux-i2c@vger.kernel.org, devicetree@vger.kernel.org,
	dillon min <dillon.minfei@gmail.com>
Subject: [PATCH v4 4/4] i2c: stm32f4: Fix stmpe811 get xyz data timeout issue
Date: Tue,  9 Jun 2020 21:26:43 +0800	[thread overview]
Message-ID: <1591709203-12106-5-git-send-email-dillon.minfei@gmail.com> (raw)
In-Reply-To: <1591709203-12106-1-git-send-email-dillon.minfei@gmail.com>

From: dillon min <dillon.minfei@gmail.com>

as stm32f429's internal flash is 2Mbytes and compiled kernel
image bigger than 2Mbytes, so we have to load kernel image
to sdram on stm32f429-disco board which has 8Mbytes sdram space.

based on above context, as you knows kernel running on external
sdram is more slower than internal flash. besides, we need read 4
bytes to get touch screen xyz(x, y, pressure) coordinate data in
stmpe811 interrupt.

so, in stm32f4_i2c_handle_rx_done, as i2c read slower than running
in xip mode, have to adjust 'STOP/START bit set position' from last
two bytes to last one bytes. else, will get i2c timeout in reading
touch screen coordinate.

to not take side effect, introduce IIC_LAST_BYTE_POS to support xip
kernel or has mmu platform.

Signed-off-by: dillon min <dillon.minfei@gmail.com>
---

V4: indroduce 'IIC_LAST_BYTE_POS' to compatible with xipkernel boot

 drivers/i2c/busses/i2c-stm32f4.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-stm32f4.c b/drivers/i2c/busses/i2c-stm32f4.c
index d6a69dfcac3f..97cf42ae7fa0 100644
--- a/drivers/i2c/busses/i2c-stm32f4.c
+++ b/drivers/i2c/busses/i2c-stm32f4.c
@@ -93,6 +93,12 @@
 #define STM32F4_I2C_MAX_FREQ		46U
 #define HZ_TO_MHZ			1000000
 
+#if !defined(CONFIG_MMU) && !defined(CONFIG_XIP_KERNEL)
+#define IIC_LAST_BYTE_POS 1
+#else
+#define IIC_LAST_BYTE_POS 2
+#endif
+
 /**
  * struct stm32f4_i2c_msg - client specific data
  * @addr: 8-bit slave addr, including r/w bit
@@ -439,7 +445,7 @@ static void stm32f4_i2c_handle_rx_done(struct stm32f4_i2c_dev *i2c_dev)
 	int i;
 
 	switch (msg->count) {
-	case 2:
+	case IIC_LAST_BYTE_POS:
 		/*
 		 * In order to correctly send the Stop or Repeated Start
 		 * condition on the I2C bus, the STOP/START bit has to be set
@@ -454,7 +460,7 @@ static void stm32f4_i2c_handle_rx_done(struct stm32f4_i2c_dev *i2c_dev)
 		else
 			stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_START);
 
-		for (i = 2; i > 0; i--)
+		for (i = IIC_LAST_BYTE_POS; i > 0; i--)
 			stm32f4_i2c_read_msg(i2c_dev);
 
 		reg = i2c_dev->base + STM32F4_I2C_CR2;
@@ -463,7 +469,7 @@ static void stm32f4_i2c_handle_rx_done(struct stm32f4_i2c_dev *i2c_dev)
 
 		complete(&i2c_dev->complete);
 		break;
-	case 3:
+	case (IIC_LAST_BYTE_POS+1):
 		/*
 		 * In order to correctly generate the NACK pulse after the last
 		 * received data byte, we have to enable NACK before reading N-2
-- 
2.7.4


WARNING: multiple messages have this Message-ID (diff)
From: dillon.minfei@gmail.com
To: robh+dt@kernel.org, mcoquelin.stm32@gmail.com,
	alexandre.torgue@st.com, p.zabel@pengutronix.de,
	pierre-yves.mordret@st.com, philippe.schenker@toradex.com
Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-i2c@vger.kernel.org, dillon min <dillon.minfei@gmail.com>,
	linux-stm32@st-md-mailman.stormreply.com,
	linux-arm-kernel@lists.infradead.org
Subject: [PATCH v4 4/4] i2c: stm32f4: Fix stmpe811 get xyz data timeout issue
Date: Tue,  9 Jun 2020 21:26:43 +0800	[thread overview]
Message-ID: <1591709203-12106-5-git-send-email-dillon.minfei@gmail.com> (raw)
In-Reply-To: <1591709203-12106-1-git-send-email-dillon.minfei@gmail.com>

From: dillon min <dillon.minfei@gmail.com>

as stm32f429's internal flash is 2Mbytes and compiled kernel
image bigger than 2Mbytes, so we have to load kernel image
to sdram on stm32f429-disco board which has 8Mbytes sdram space.

based on above context, as you knows kernel running on external
sdram is more slower than internal flash. besides, we need read 4
bytes to get touch screen xyz(x, y, pressure) coordinate data in
stmpe811 interrupt.

so, in stm32f4_i2c_handle_rx_done, as i2c read slower than running
in xip mode, have to adjust 'STOP/START bit set position' from last
two bytes to last one bytes. else, will get i2c timeout in reading
touch screen coordinate.

to not take side effect, introduce IIC_LAST_BYTE_POS to support xip
kernel or has mmu platform.

Signed-off-by: dillon min <dillon.minfei@gmail.com>
---

V4: indroduce 'IIC_LAST_BYTE_POS' to compatible with xipkernel boot

 drivers/i2c/busses/i2c-stm32f4.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-stm32f4.c b/drivers/i2c/busses/i2c-stm32f4.c
index d6a69dfcac3f..97cf42ae7fa0 100644
--- a/drivers/i2c/busses/i2c-stm32f4.c
+++ b/drivers/i2c/busses/i2c-stm32f4.c
@@ -93,6 +93,12 @@
 #define STM32F4_I2C_MAX_FREQ		46U
 #define HZ_TO_MHZ			1000000
 
+#if !defined(CONFIG_MMU) && !defined(CONFIG_XIP_KERNEL)
+#define IIC_LAST_BYTE_POS 1
+#else
+#define IIC_LAST_BYTE_POS 2
+#endif
+
 /**
  * struct stm32f4_i2c_msg - client specific data
  * @addr: 8-bit slave addr, including r/w bit
@@ -439,7 +445,7 @@ static void stm32f4_i2c_handle_rx_done(struct stm32f4_i2c_dev *i2c_dev)
 	int i;
 
 	switch (msg->count) {
-	case 2:
+	case IIC_LAST_BYTE_POS:
 		/*
 		 * In order to correctly send the Stop or Repeated Start
 		 * condition on the I2C bus, the STOP/START bit has to be set
@@ -454,7 +460,7 @@ static void stm32f4_i2c_handle_rx_done(struct stm32f4_i2c_dev *i2c_dev)
 		else
 			stm32f4_i2c_set_bits(reg, STM32F4_I2C_CR1_START);
 
-		for (i = 2; i > 0; i--)
+		for (i = IIC_LAST_BYTE_POS; i > 0; i--)
 			stm32f4_i2c_read_msg(i2c_dev);
 
 		reg = i2c_dev->base + STM32F4_I2C_CR2;
@@ -463,7 +469,7 @@ static void stm32f4_i2c_handle_rx_done(struct stm32f4_i2c_dev *i2c_dev)
 
 		complete(&i2c_dev->complete);
 		break;
-	case 3:
+	case (IIC_LAST_BYTE_POS+1):
 		/*
 		 * In order to correctly generate the NACK pulse after the last
 		 * received data byte, we have to enable NACK before reading N-2
-- 
2.7.4


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  parent reply	other threads:[~2020-06-09 13:27 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-09 13:26 [PATCH v4 0/4] Enable stmpe811 touch screen on stm32f429-disco board dillon.minfei
2020-06-09 13:26 ` dillon.minfei
2020-06-09 13:26 ` [PATCH v4 1/4] ARM: dts: stm32: add I2C3 support on STM32F429 SoC dillon.minfei
2020-06-09 13:26   ` dillon.minfei
2020-06-09 13:26 ` [PATCH v4 2/4] ARM: dts: stm32: Add pin map for I2C3 controller on stm32f4 dillon.minfei
2020-06-09 13:26   ` dillon.minfei
2020-06-09 13:26 ` [PATCH v4 3/4] ARM: dts: stm32: enable stmpe811 on stm32429-disco board dillon.minfei
2020-06-09 13:26   ` dillon.minfei
2020-06-09 13:26 ` dillon.minfei [this message]
2020-06-09 13:26   ` [PATCH v4 4/4] i2c: stm32f4: Fix stmpe811 get xyz data timeout issue dillon.minfei
2021-03-15 12:43   ` dillon min
2021-03-15 12:43     ` dillon min
2021-03-15 13:00     ` Wolfram Sang
2021-03-15 13:00       ` Wolfram Sang
2021-05-07  2:54       ` dillon min
2021-05-07  2:54         ` dillon min
2021-05-07 12:29         ` [Linux-stm32] " Patrice CHOTARD
2021-05-07 12:29           ` Patrice CHOTARD
2021-05-07 12:47           ` dillon min
2021-05-07 12:47             ` dillon min
2020-06-15  9:08 ` [PATCH v4 0/4] Enable stmpe811 touch screen on stm32f429-disco board Alexandre Torgue
2020-06-15  9:08   ` Alexandre Torgue
2020-06-15 10:06   ` dillon min
2020-06-15 10:06     ` dillon min

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1591709203-12106-5-git-send-email-dillon.minfei@gmail.com \
    --to=dillon.minfei@gmail.com \
    --cc=alexandre.torgue@st.com \
    --cc=devicetree@vger.kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-i2c@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-stm32@st-md-mailman.stormreply.com \
    --cc=mcoquelin.stm32@gmail.com \
    --cc=p.zabel@pengutronix.de \
    --cc=philippe.schenker@toradex.com \
    --cc=pierre-yves.mordret@st.com \
    --cc=robh+dt@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.