gpio: mpc8xxx: latch GPIOs state on module load when configured as output
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Quoted 35 lines · On Wed, May 31, 2023 at 10:41 PM <[email protected]> wrote:
From: Michal Smulski <[email protected]>
Qoriq and related devices allow reading out state of GPIO set as output. However, currently on driver's init, all outputs are configured as driven low. So, any changes to GPIO confiuration will drive all pins (configured as output) as output-low.
This patch latches state of output GPIOs before any GPIO configuration takes place. This preserves any output settings done prior to loading the driver (for example, by u-boot).Signed-off-by Michal Smulski <[email protected]>--- drivers/gpio/gpio-mpc8xxx.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)drivers/gpio/gpio-mpc8xxx.c +5
-2@@ -375,8 +375,12 @@ static int mpc8xxx_probe(struct platform_device *pdev)if (of_device_is_compatible (np,"fsl,qoriq-gpio" ) ||of_device_is_compatible (np,"fsl,ls1028a-gpio" ) ||of_device_is_compatible (np,"fsl,ls1088a-gpio" ) || -is_acpi_node (fwnode)) +is_acpi_node (fwnode)) { gc->write_reg (mpc8xxx_gc->regs +GPIO_IBE ,0xffffffff ); +/* Also, latch state of GPIOs configured as output by bootloader. */ + gc->bgpio_data = gc->read_reg (mpc8xxx_gc->regs +GPIO_DAT ) & + gc->read_reg (mpc8xxx_gc->regs +GPIO_DIR ); + } ret =devm_gpiochip_add_data (&pdev->dev, gc, mpc8xxx_gc);if (ret) { --
Quoted 2 lines
2.34.1
When sending a new version, please list the changes since the last submission.
Bart
Yes, I will re-send version v2 with cover letter.
Regards,
Michal
-----Original Message-----
From: Bartosz Golaszewski <[email protected]>
Sent: Thursday, June 1, 2023 12:37 AM
To: [email protected]
Cc: [email protected]; [email protected]; Michal Smulski <[email protected]>
Subject: Re: [PATCH v2] gpio: mpc8xxx: latch GPIOs state on module load when configured as output
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Quoted 35 lines · On Wed, May 31, 2023 at 10:41 PM <[email protected]> wrote:
From: Michal Smulski <[email protected]>
Qoriq and related devices allow reading out state of GPIO set as output. However, currently on driver's init, all outputs are configured as driven low. So, any changes to GPIO confiuration will drive all pins (configured as output) as output-low.
This patch latches state of output GPIOs before any GPIO configuration takes place. This preserves any output settings done prior to loading the driver (for example, by u-boot).Signed-off-by Michal Smulski <[email protected]>--- drivers/gpio/gpio-mpc8xxx.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)drivers/gpio/gpio-mpc8xxx.c +5
-2@@ -375,8 +375,12 @@ static int mpc8xxx_probe(struct platform_device *pdev)if (of_device_is_compatible (np,"fsl,qoriq-gpio" ) ||of_device_is_compatible (np,"fsl,ls1028a-gpio" ) ||of_device_is_compatible (np,"fsl,ls1088a-gpio" ) || -is_acpi_node (fwnode)) +is_acpi_node (fwnode)) { gc->write_reg (mpc8xxx_gc->regs +GPIO_IBE ,0xffffffff ); +/* Also, latch state of GPIOs configured as output by bootloader. */ + gc->bgpio_data = gc->read_reg (mpc8xxx_gc->regs +GPIO_DAT ) & + gc->read_reg (mpc8xxx_gc->regs +GPIO_DIR ); + } ret =devm_gpiochip_add_data (&pdev->dev, gc, mpc8xxx_gc);if (ret) { --
Quoted 2 lines
2.34.1
When sending a new version, please list the changes since the last submission.
Bart