From 8299d1f057439f94c6a4412e2e5c5082b82a30c9 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= Date: Sat, 21 Aug 2021 10:54:34 +0200 Subject: bcm27xx: add kernel 5.10 support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Rebased RPi foundation patches on linux 5.10.59, removed applied and reverted patches, wireless patches and defconfig patches. bcm2708: boot tested on RPi B+ v1.2 bcm2709: boot tested on RPi 4B v1.1 4G bcm2711: boot tested on RPi 4B v1.1 4G Signed-off-by: Álvaro Fernández Rojas --- ...aspberrypi-touchscreen-Use-independent-I2.patch | 58 ++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 target/linux/bcm27xx/patches-5.10/950-0382-drm-panel-raspberrypi-touchscreen-Use-independent-I2.patch (limited to 'target/linux/bcm27xx/patches-5.10/950-0382-drm-panel-raspberrypi-touchscreen-Use-independent-I2.patch') diff --git a/target/linux/bcm27xx/patches-5.10/950-0382-drm-panel-raspberrypi-touchscreen-Use-independent-I2.patch b/target/linux/bcm27xx/patches-5.10/950-0382-drm-panel-raspberrypi-touchscreen-Use-independent-I2.patch new file mode 100644 index 0000000000..57aabc7e87 --- /dev/null +++ b/target/linux/bcm27xx/patches-5.10/950-0382-drm-panel-raspberrypi-touchscreen-Use-independent-I2.patch @@ -0,0 +1,58 @@ +From 3ad3a680ece56c7134d9500a0413b4f9259c07d8 Mon Sep 17 00:00:00 2001 +From: Dave Stevenson +Date: Thu, 23 Apr 2020 10:17:18 +0100 +Subject: [PATCH] drm/panel/raspberrypi-touchscreen: Use independent + I2C actions with delay. + +We now have the hardware I2C controller pinmuxed to the drive the +display I2C, but this controller does not support clock stretching. +The Atmel micro-controller in the panel requires clock stretching +to allow it to prepare any data to be read. + +Split the rpi_touchscreen_i2c_read into two independent transactions with +a delay between them for the Atmel to prepare the data. + +Signed-off-by: Dave Stevenson +--- + .../drm/panel/panel-raspberrypi-touchscreen.c | 30 ++++++++++++++++++- + 1 file changed, 29 insertions(+), 1 deletion(-) + +--- a/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c ++++ b/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c +@@ -219,7 +219,35 @@ static struct rpi_touchscreen *panel_to_ + + static int rpi_touchscreen_i2c_read(struct rpi_touchscreen *ts, u8 reg) + { +- return i2c_smbus_read_byte_data(ts->i2c, reg); ++ struct i2c_client *client = ts->i2c; ++ struct i2c_msg msgs[1]; ++ u8 addr_buf[1] = { reg }; ++ u8 data_buf[1] = { 0, }; ++ int ret; ++ ++ /* Write register address */ ++ msgs[0].addr = client->addr; ++ msgs[0].flags = 0; ++ msgs[0].len = ARRAY_SIZE(addr_buf); ++ msgs[0].buf = addr_buf; ++ ++ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); ++ if (ret != ARRAY_SIZE(msgs)) ++ return -EIO; ++ ++ usleep_range(100, 300); ++ ++ /* Read data from register */ ++ msgs[0].addr = client->addr; ++ msgs[0].flags = I2C_M_RD; ++ msgs[0].len = 1; ++ msgs[0].buf = data_buf; ++ ++ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); ++ if (ret != ARRAY_SIZE(msgs)) ++ return -EIO; ++ ++ return data_buf[0]; + } + + static void rpi_touchscreen_i2c_write(struct rpi_touchscreen *ts, -- cgit v1.2.3