* [PATCH v3 0/2] Add CTS/RTS gpio support to STM32 UART @ 2020-04-20 17:02 mani 2020-04-20 17:02 ` [PATCH v3 1/2] dt-bindings: serial: Document CTS/RTS gpios in " mani ` (2 more replies) 0 siblings, 3 replies; 9+ messages in thread From: mani @ 2020-04-20 17:02 UTC (permalink / raw) To: gregkh, robh+dt, mcoquelin.stm32, alexandre.torgue Cc: linux-serial, devicetree, linux-stm32, linux-arm-kernel, linux-kernel, fabrice.gasnier, andy.shevchenko, Manivannan Sadhasivam From: Manivannan Sadhasivam <mani@kernel.org> Hello, This patchset adds CTS/RTS gpio support to STM32 UART controller. Eventhough the UART controller supports using dedicated CTS/RTS gpios, sometimes we need to use different set of gpios for flow control. This is necessary for the upcoming STM32MP1 based board called Stinger96 IoT-Box. On that board, a bluetooth chip is connected to one of the UART controller but the CTS/RTS lines got swapped mistakenly. So this patchset serves as a workaround for that hardware bug and also supports the usecase of using any gpio for CTS/RTS functionality. As per the sugggestion provided by Andy for v1, I've now switched to mctrl_gpio driver. This patchset has been validated with Stinger96 IoT-Box connected to Murata WiFi-BT combo chip. Thanks, Mani Changes in v3: * Added Andy's reviewed-by tag * Fixed minor issues spotted by Fabrice Changes in v2: As per the review by Andy: * Switched to mctrl_gpio driver instead of using custom CTS/RTS implementation * Removed the use of software flow control terminology. Manivannan Sadhasivam (2): dt-bindings: serial: Document CTS/RTS gpios in STM32 UART tty: serial: Add modem control gpio support for STM32 UART .../bindings/serial/st,stm32-uart.yaml | 14 +++++ drivers/tty/serial/Kconfig | 1 + drivers/tty/serial/stm32-usart.c | 53 ++++++++++++++++++- drivers/tty/serial/stm32-usart.h | 1 + 4 files changed, 67 insertions(+), 2 deletions(-) -- 2.17.1 ^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v3 1/2] dt-bindings: serial: Document CTS/RTS gpios in STM32 UART 2020-04-20 17:02 [PATCH v3 0/2] Add CTS/RTS gpio support to STM32 UART mani @ 2020-04-20 17:02 ` mani 2020-05-06 19:59 ` Rob Herring 2020-05-18 7:04 ` Geert Uytterhoeven 2020-04-20 17:02 ` [PATCH v3 2/2] tty: serial: Add modem control gpio support for " mani 2020-05-07 14:07 ` [PATCH v3 0/2] Add CTS/RTS gpio support to " Manivannan Sadhasivam 2 siblings, 2 replies; 9+ messages in thread From: mani @ 2020-04-20 17:02 UTC (permalink / raw) To: gregkh, robh+dt, mcoquelin.stm32, alexandre.torgue Cc: linux-serial, devicetree, linux-stm32, linux-arm-kernel, linux-kernel, fabrice.gasnier, andy.shevchenko, Manivannan Sadhasivam From: Manivannan Sadhasivam <mani@kernel.org> Document the use of CTS/RTS gpios for flow control in STM32 UART controller. These properties can be used instead of 'st,hw-flow-ctrl' for making use of any gpio pins for flow control instead of dedicated pins. It should be noted that both CTS/RTS and 'st,hw-flow-ctrl' properties cannot co-exist in a design. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> --- .../devicetree/bindings/serial/st,stm32-uart.yaml | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/Documentation/devicetree/bindings/serial/st,stm32-uart.yaml b/Documentation/devicetree/bindings/serial/st,stm32-uart.yaml index 238c44192d31..75b8521eb7cb 100644 --- a/Documentation/devicetree/bindings/serial/st,stm32-uart.yaml +++ b/Documentation/devicetree/bindings/serial/st,stm32-uart.yaml @@ -48,6 +48,12 @@ properties: minItems: 1 maxItems: 2 + cts-gpios: + maxItems: 1 + + rts-gpios: + maxItems: 1 + wakeup-source: true rs485-rts-delay: true @@ -55,6 +61,14 @@ properties: linux,rs485-enabled-at-boot-time: true rs485-rx-during-tx: true +if: + required: + - st,hw-flow-ctrl +then: + properties: + cts-gpios: false + rts-gpios: false + required: - compatible - reg -- 2.17.1 ^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH v3 1/2] dt-bindings: serial: Document CTS/RTS gpios in STM32 UART 2020-04-20 17:02 ` [PATCH v3 1/2] dt-bindings: serial: Document CTS/RTS gpios in " mani @ 2020-05-06 19:59 ` Rob Herring 2020-05-18 7:04 ` Geert Uytterhoeven 1 sibling, 0 replies; 9+ messages in thread From: Rob Herring @ 2020-05-06 19:59 UTC (permalink / raw) To: mani Cc: gregkh, robh+dt, mcoquelin.stm32, alexandre.torgue, devicetree, Manivannan Sadhasivam, linux-kernel, andy.shevchenko, linux-serial, fabrice.gasnier, linux-stm32, linux-arm-kernel On Mon, 20 Apr 2020 22:32:03 +0530, mani@kernel.org wrote: > From: Manivannan Sadhasivam <mani@kernel.org> > > Document the use of CTS/RTS gpios for flow control in STM32 UART > controller. These properties can be used instead of 'st,hw-flow-ctrl' > for making use of any gpio pins for flow control instead of dedicated > pins. It should be noted that both CTS/RTS and 'st,hw-flow-ctrl' > properties cannot co-exist in a design. > > Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> > Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> > --- > .../devicetree/bindings/serial/st,stm32-uart.yaml | 14 ++++++++++++++ > 1 file changed, 14 insertions(+) > Reviewed-by: Rob Herring <robh@kernel.org> ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v3 1/2] dt-bindings: serial: Document CTS/RTS gpios in STM32 UART 2020-04-20 17:02 ` [PATCH v3 1/2] dt-bindings: serial: Document CTS/RTS gpios in " mani 2020-05-06 19:59 ` Rob Herring @ 2020-05-18 7:04 ` Geert Uytterhoeven 2020-05-18 7:25 ` [Linux-stm32] " Erwan LE RAY 1 sibling, 1 reply; 9+ messages in thread From: Geert Uytterhoeven @ 2020-05-18 7:04 UTC (permalink / raw) To: mani Cc: Greg KH, Rob Herring, Maxime Coquelin, Alexandre Torgue, open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS, Linux Kernel Mailing List, Andy Shevchenko, open list:SERIAL DRIVERS, fabrice.gasnier, linux-stm32, Linux ARM Hi Mani, On Mon, Apr 20, 2020 at 7:02 PM <mani@kernel.org> wrote: > From: Manivannan Sadhasivam <mani@kernel.org> > > Document the use of CTS/RTS gpios for flow control in STM32 UART > controller. These properties can be used instead of 'st,hw-flow-ctrl' > for making use of any gpio pins for flow control instead of dedicated > pins. It should be noted that both CTS/RTS and 'st,hw-flow-ctrl' > properties cannot co-exist in a design. > > Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> > Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> > --- a/Documentation/devicetree/bindings/serial/st,stm32-uart.yaml > +++ b/Documentation/devicetree/bindings/serial/st,stm32-uart.yaml > @@ -55,6 +61,14 @@ properties: > linux,rs485-enabled-at-boot-time: true > rs485-rx-during-tx: true > > +if: > + required: > + - st,hw-flow-ctrl Perhaps "st,hw-flow-ctrl" should be deprecated, in favor of the standard "uart-has-rtscts" property? Of course the driver needs to gain support for the latter first. > +then: > + properties: > + cts-gpios: false > + rts-gpios: false > + > required: > - compatible > - reg Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [Linux-stm32] [PATCH v3 1/2] dt-bindings: serial: Document CTS/RTS gpios in STM32 UART 2020-05-18 7:04 ` Geert Uytterhoeven @ 2020-05-18 7:25 ` Erwan LE RAY 0 siblings, 0 replies; 9+ messages in thread From: Erwan LE RAY @ 2020-05-18 7:25 UTC (permalink / raw) To: Geert Uytterhoeven, mani Cc: open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS, Greg KH, Linux Kernel Mailing List, Andy Shevchenko, Rob Herring, Maxime Coquelin, open list:SERIAL DRIVERS, Fabrice GASNIER, linux-stm32, Linux ARM Hi Geert, On 5/18/20 9:04 AM, Geert Uytterhoeven wrote: > Hi Mani, > > On Mon, Apr 20, 2020 at 7:02 PM <mani@kernel.org> wrote: >> From: Manivannan Sadhasivam <mani@kernel.org> >> >> Document the use of CTS/RTS gpios for flow control in STM32 UART >> controller. These properties can be used instead of 'st,hw-flow-ctrl' >> for making use of any gpio pins for flow control instead of dedicated >> pins. It should be noted that both CTS/RTS and 'st,hw-flow-ctrl' >> properties cannot co-exist in a design. >> >> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> >> Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> >> --- a/Documentation/devicetree/bindings/serial/st,stm32-uart.yaml >> +++ b/Documentation/devicetree/bindings/serial/st,stm32-uart.yaml >> @@ -55,6 +61,14 @@ properties: >> linux,rs485-enabled-at-boot-time: true >> rs485-rx-during-tx: true >> >> +if: >> + required: >> + - st,hw-flow-ctrl > Perhaps "st,hw-flow-ctrl" should be deprecated, in favor of the standard > "uart-has-rtscts" property? > Of course the driver needs to gain support for the latter first. You're fully right, the patch to deprecate "st, hw-flow-ctrl" and introduce generic "uart-has-rtscts" property in the driver is ready and will be sent this week on top of Mani patch. > >> +then: >> + properties: >> + cts-gpios: false >> + rts-gpios: false >> + >> required: >> - compatible >> - reg > Gr{oetje,eeting}s, > > Geert > ^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v3 2/2] tty: serial: Add modem control gpio support for STM32 UART 2020-04-20 17:02 [PATCH v3 0/2] Add CTS/RTS gpio support to STM32 UART mani 2020-04-20 17:02 ` [PATCH v3 1/2] dt-bindings: serial: Document CTS/RTS gpios in " mani @ 2020-04-20 17:02 ` mani 2020-04-21 12:58 ` Fabrice Gasnier 2020-05-07 14:07 ` [PATCH v3 0/2] Add CTS/RTS gpio support to " Manivannan Sadhasivam 2 siblings, 1 reply; 9+ messages in thread From: mani @ 2020-04-20 17:02 UTC (permalink / raw) To: gregkh, robh+dt, mcoquelin.stm32, alexandre.torgue Cc: linux-serial, devicetree, linux-stm32, linux-arm-kernel, linux-kernel, fabrice.gasnier, andy.shevchenko, Manivannan Sadhasivam From: Manivannan Sadhasivam <mani@kernel.org> STM32 UART controllers have the built in modem control support using dedicated gpios which can be enabled using 'st,hw-flow-ctrl' flag in DT. But there might be cases where the board design need to use different gpios for modem control. For supporting such cases, this commit adds modem control gpio support to STM32 UART controller using mctrl_gpio driver. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> --- drivers/tty/serial/Kconfig | 1 + drivers/tty/serial/stm32-usart.c | 53 ++++++++++++++++++++++++++++++-- drivers/tty/serial/stm32-usart.h | 1 + 3 files changed, 53 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 0aea76cd67ff..e7a6f2130684 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -1462,6 +1462,7 @@ config SERIAL_STM32 tristate "STMicroelectronics STM32 serial port support" select SERIAL_CORE depends on ARCH_STM32 || COMPILE_TEST + select SERIAL_MCTRL_GPIO if GPIOLIB help This driver is for the on-chip Serial Controller on STMicroelectronics STM32 MCUs. diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index 5e93e8d40f59..17c2f3276888 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -31,6 +31,7 @@ #include <linux/tty_flip.h> #include <linux/tty.h> +#include "serial_mctrl_gpio.h" #include "stm32-usart.h" static void stm32_stop_tx(struct uart_port *port); @@ -510,12 +511,29 @@ static void stm32_set_mctrl(struct uart_port *port, unsigned int mctrl) stm32_set_bits(port, ofs->cr3, USART_CR3_RTSE); else stm32_clr_bits(port, ofs->cr3, USART_CR3_RTSE); + + mctrl_gpio_set(stm32_port->gpios, mctrl); } static unsigned int stm32_get_mctrl(struct uart_port *port) { + struct stm32_port *stm32_port = to_stm32_port(port); + unsigned int ret; + /* This routine is used to get signals of: DCD, DSR, RI, and CTS */ - return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; + ret = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; + + return mctrl_gpio_get(stm32_port->gpios, &ret); +} + +static void stm32_enable_ms(struct uart_port *port) +{ + mctrl_gpio_enable_ms(to_stm32_port(port)->gpios); +} + +static void stm32_disable_ms(struct uart_port *port) +{ + mctrl_gpio_disable_ms(to_stm32_port(port)->gpios); } /* Transmit stop */ @@ -626,6 +644,9 @@ static void stm32_shutdown(struct uart_port *port) u32 val, isr; int ret; + /* Disable modem control interrupts */ + stm32_disable_ms(port); + val = USART_CR1_TXEIE | USART_CR1_TE; val |= stm32_port->cr1_irq | USART_CR1_RE; val |= BIT(cfg->uart_enable_bit); @@ -764,6 +785,12 @@ static void stm32_set_termios(struct uart_port *port, struct ktermios *termios, cr3 |= USART_CR3_CTSE | USART_CR3_RTSE; } + /* Handle modem control interrupts */ + if (UART_ENABLE_MS(port, termios->c_cflag)) + stm32_enable_ms(port); + else + stm32_disable_ms(port); + usartdiv = DIV_ROUND_CLOSEST(port->uartclk, baud); /* @@ -898,6 +925,7 @@ static const struct uart_ops stm32_uart_ops = { .throttle = stm32_throttle, .unthrottle = stm32_unthrottle, .stop_rx = stm32_stop_rx, + .enable_ms = stm32_enable_ms, .break_ctl = stm32_break_ctl, .startup = stm32_startup, .shutdown = stm32_shutdown, @@ -960,10 +988,31 @@ static int stm32_init_port(struct stm32_port *stm32port, stm32port->port.uartclk = clk_get_rate(stm32port->clk); if (!stm32port->port.uartclk) { - clk_disable_unprepare(stm32port->clk); ret = -EINVAL; + goto err_clk; + } + + stm32port->gpios = mctrl_gpio_init(&stm32port->port, 0); + if (IS_ERR(stm32port->gpios)) { + ret = PTR_ERR(stm32port->gpios); + goto err_clk; } + /* Both CTS/RTS gpios and "st,hw-flow-ctrl" should not be specified */ + if (stm32port->hw_flow_control) { + if (mctrl_gpio_to_gpiod(stm32port->gpios, UART_GPIO_CTS) || + mctrl_gpio_to_gpiod(stm32port->gpios, UART_GPIO_RTS)) { + dev_err(&pdev->dev, "Conflicting RTS/CTS config\n"); + ret = -EINVAL; + goto err_clk; + } + } + + return ret; + +err_clk: + clk_disable_unprepare(stm32port->clk); + return ret; } diff --git a/drivers/tty/serial/stm32-usart.h b/drivers/tty/serial/stm32-usart.h index db8bf0d4982d..d4c916e78d40 100644 --- a/drivers/tty/serial/stm32-usart.h +++ b/drivers/tty/serial/stm32-usart.h @@ -274,6 +274,7 @@ struct stm32_port { bool fifoen; int wakeirq; int rdr_mask; /* receive data register mask */ + struct mctrl_gpios *gpios; /* modem control gpios */ }; static struct stm32_port stm32_ports[STM32_MAX_PORTS]; -- 2.17.1 ^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH v3 2/2] tty: serial: Add modem control gpio support for STM32 UART 2020-04-20 17:02 ` [PATCH v3 2/2] tty: serial: Add modem control gpio support for " mani @ 2020-04-21 12:58 ` Fabrice Gasnier 0 siblings, 0 replies; 9+ messages in thread From: Fabrice Gasnier @ 2020-04-21 12:58 UTC (permalink / raw) To: mani Cc: gregkh, robh+dt, mcoquelin.stm32, alexandre.torgue, devicetree, linux-kernel, andy.shevchenko, linux-serial, linux-stm32, linux-arm-kernel On 4/20/20 7:02 PM, mani@kernel.org wrote: > From: Manivannan Sadhasivam <mani@kernel.org> > > STM32 UART controllers have the built in modem control support using > dedicated gpios which can be enabled using 'st,hw-flow-ctrl' flag in DT. > But there might be cases where the board design need to use different > gpios for modem control. > > For supporting such cases, this commit adds modem control gpio support > to STM32 UART controller using mctrl_gpio driver. > > Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> > Signed-off-by: Manivannan Sadhasivam <mani@kernel.org> > --- > drivers/tty/serial/Kconfig | 1 + > drivers/tty/serial/stm32-usart.c | 53 ++++++++++++++++++++++++++++++-- > drivers/tty/serial/stm32-usart.h | 1 + > 3 files changed, 53 insertions(+), 2 deletions(-) Hi Mani, You can add my: Acked-by: Fabrice Gasnier <fabrice.gasnier@st.com> Thanks, Fabrice > > diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig > index 0aea76cd67ff..e7a6f2130684 100644 > --- a/drivers/tty/serial/Kconfig > +++ b/drivers/tty/serial/Kconfig > @@ -1462,6 +1462,7 @@ config SERIAL_STM32 > tristate "STMicroelectronics STM32 serial port support" > select SERIAL_CORE > depends on ARCH_STM32 || COMPILE_TEST > + select SERIAL_MCTRL_GPIO if GPIOLIB > help > This driver is for the on-chip Serial Controller on > STMicroelectronics STM32 MCUs. > diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c > index 5e93e8d40f59..17c2f3276888 100644 > --- a/drivers/tty/serial/stm32-usart.c > +++ b/drivers/tty/serial/stm32-usart.c > @@ -31,6 +31,7 @@ > #include <linux/tty_flip.h> > #include <linux/tty.h> > > +#include "serial_mctrl_gpio.h" > #include "stm32-usart.h" > > static void stm32_stop_tx(struct uart_port *port); > @@ -510,12 +511,29 @@ static void stm32_set_mctrl(struct uart_port *port, unsigned int mctrl) > stm32_set_bits(port, ofs->cr3, USART_CR3_RTSE); > else > stm32_clr_bits(port, ofs->cr3, USART_CR3_RTSE); > + > + mctrl_gpio_set(stm32_port->gpios, mctrl); > } > > static unsigned int stm32_get_mctrl(struct uart_port *port) > { > + struct stm32_port *stm32_port = to_stm32_port(port); > + unsigned int ret; > + > /* This routine is used to get signals of: DCD, DSR, RI, and CTS */ > - return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; > + ret = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; > + > + return mctrl_gpio_get(stm32_port->gpios, &ret); > +} > + > +static void stm32_enable_ms(struct uart_port *port) > +{ > + mctrl_gpio_enable_ms(to_stm32_port(port)->gpios); > +} > + > +static void stm32_disable_ms(struct uart_port *port) > +{ > + mctrl_gpio_disable_ms(to_stm32_port(port)->gpios); > } > > /* Transmit stop */ > @@ -626,6 +644,9 @@ static void stm32_shutdown(struct uart_port *port) > u32 val, isr; > int ret; > > + /* Disable modem control interrupts */ > + stm32_disable_ms(port); > + > val = USART_CR1_TXEIE | USART_CR1_TE; > val |= stm32_port->cr1_irq | USART_CR1_RE; > val |= BIT(cfg->uart_enable_bit); > @@ -764,6 +785,12 @@ static void stm32_set_termios(struct uart_port *port, struct ktermios *termios, > cr3 |= USART_CR3_CTSE | USART_CR3_RTSE; > } > > + /* Handle modem control interrupts */ > + if (UART_ENABLE_MS(port, termios->c_cflag)) > + stm32_enable_ms(port); > + else > + stm32_disable_ms(port); > + > usartdiv = DIV_ROUND_CLOSEST(port->uartclk, baud); > > /* > @@ -898,6 +925,7 @@ static const struct uart_ops stm32_uart_ops = { > .throttle = stm32_throttle, > .unthrottle = stm32_unthrottle, > .stop_rx = stm32_stop_rx, > + .enable_ms = stm32_enable_ms, > .break_ctl = stm32_break_ctl, > .startup = stm32_startup, > .shutdown = stm32_shutdown, > @@ -960,10 +988,31 @@ static int stm32_init_port(struct stm32_port *stm32port, > > stm32port->port.uartclk = clk_get_rate(stm32port->clk); > if (!stm32port->port.uartclk) { > - clk_disable_unprepare(stm32port->clk); > ret = -EINVAL; > + goto err_clk; > + } > + > + stm32port->gpios = mctrl_gpio_init(&stm32port->port, 0); > + if (IS_ERR(stm32port->gpios)) { > + ret = PTR_ERR(stm32port->gpios); > + goto err_clk; > } > > + /* Both CTS/RTS gpios and "st,hw-flow-ctrl" should not be specified */ > + if (stm32port->hw_flow_control) { > + if (mctrl_gpio_to_gpiod(stm32port->gpios, UART_GPIO_CTS) || > + mctrl_gpio_to_gpiod(stm32port->gpios, UART_GPIO_RTS)) { > + dev_err(&pdev->dev, "Conflicting RTS/CTS config\n"); > + ret = -EINVAL; > + goto err_clk; > + } > + } > + > + return ret; > + > +err_clk: > + clk_disable_unprepare(stm32port->clk); > + > return ret; > } > > diff --git a/drivers/tty/serial/stm32-usart.h b/drivers/tty/serial/stm32-usart.h > index db8bf0d4982d..d4c916e78d40 100644 > --- a/drivers/tty/serial/stm32-usart.h > +++ b/drivers/tty/serial/stm32-usart.h > @@ -274,6 +274,7 @@ struct stm32_port { > bool fifoen; > int wakeirq; > int rdr_mask; /* receive data register mask */ > + struct mctrl_gpios *gpios; /* modem control gpios */ > }; > > static struct stm32_port stm32_ports[STM32_MAX_PORTS]; > ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v3 0/2] Add CTS/RTS gpio support to STM32 UART 2020-04-20 17:02 [PATCH v3 0/2] Add CTS/RTS gpio support to STM32 UART mani 2020-04-20 17:02 ` [PATCH v3 1/2] dt-bindings: serial: Document CTS/RTS gpios in " mani 2020-04-20 17:02 ` [PATCH v3 2/2] tty: serial: Add modem control gpio support for " mani @ 2020-05-07 14:07 ` Manivannan Sadhasivam 2020-05-07 15:34 ` Greg KH 2 siblings, 1 reply; 9+ messages in thread From: Manivannan Sadhasivam @ 2020-05-07 14:07 UTC (permalink / raw) To: gregkh Cc: linux-serial, devicetree, linux-stm32, linux-arm-kernel, linux-kernel, fabrice.gasnier, andy.shevchenko, robh+dt, mcoquelin.stm32, alexandre.torgue Hi Greg, On Mon, Apr 20, 2020 at 10:32:02PM +0530, mani@kernel.org wrote: > From: Manivannan Sadhasivam <mani@kernel.org> > > Hello, > > This patchset adds CTS/RTS gpio support to STM32 UART controller. > Eventhough the UART controller supports using dedicated CTS/RTS gpios, > sometimes we need to use different set of gpios for flow control. > > This is necessary for the upcoming STM32MP1 based board called Stinger96 > IoT-Box. On that board, a bluetooth chip is connected to one of the UART > controller but the CTS/RTS lines got swapped mistakenly. So this patchset > serves as a workaround for that hardware bug and also supports the > usecase of using any gpio for CTS/RTS functionality. As per the sugggestion > provided by Andy for v1, I've now switched to mctrl_gpio driver. > > This patchset has been validated with Stinger96 IoT-Box connected to Murata > WiFi-BT combo chip. > Are you planning to take this series for 5.8? Thanks, Mani > Thanks, > Mani > > Changes in v3: > > * Added Andy's reviewed-by tag > * Fixed minor issues spotted by Fabrice > > Changes in v2: > > As per the review by Andy: > > * Switched to mctrl_gpio driver instead of using custom CTS/RTS > implementation > * Removed the use of software flow control terminology. > > Manivannan Sadhasivam (2): > dt-bindings: serial: Document CTS/RTS gpios in STM32 UART > tty: serial: Add modem control gpio support for STM32 UART > > .../bindings/serial/st,stm32-uart.yaml | 14 +++++ > drivers/tty/serial/Kconfig | 1 + > drivers/tty/serial/stm32-usart.c | 53 ++++++++++++++++++- > drivers/tty/serial/stm32-usart.h | 1 + > 4 files changed, 67 insertions(+), 2 deletions(-) > > -- > 2.17.1 > ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v3 0/2] Add CTS/RTS gpio support to STM32 UART 2020-05-07 14:07 ` [PATCH v3 0/2] Add CTS/RTS gpio support to " Manivannan Sadhasivam @ 2020-05-07 15:34 ` Greg KH 0 siblings, 0 replies; 9+ messages in thread From: Greg KH @ 2020-05-07 15:34 UTC (permalink / raw) To: Manivannan Sadhasivam Cc: linux-serial, devicetree, linux-stm32, linux-arm-kernel, linux-kernel, fabrice.gasnier, andy.shevchenko, robh+dt, mcoquelin.stm32, alexandre.torgue On Thu, May 07, 2020 at 07:37:50PM +0530, Manivannan Sadhasivam wrote: > Hi Greg, > > On Mon, Apr 20, 2020 at 10:32:02PM +0530, mani@kernel.org wrote: > > From: Manivannan Sadhasivam <mani@kernel.org> > > > > Hello, > > > > This patchset adds CTS/RTS gpio support to STM32 UART controller. > > Eventhough the UART controller supports using dedicated CTS/RTS gpios, > > sometimes we need to use different set of gpios for flow control. > > > > This is necessary for the upcoming STM32MP1 based board called Stinger96 > > IoT-Box. On that board, a bluetooth chip is connected to one of the UART > > controller but the CTS/RTS lines got swapped mistakenly. So this patchset > > serves as a workaround for that hardware bug and also supports the > > usecase of using any gpio for CTS/RTS functionality. As per the sugggestion > > provided by Andy for v1, I've now switched to mctrl_gpio driver. > > > > This patchset has been validated with Stinger96 IoT-Box connected to Murata > > WiFi-BT combo chip. > > > > Are you planning to take this series for 5.8? I had to wait for the DT protion to be reviewed before I could do anything. Give me some time, if it looks ok, it will go into 5.8. thanks, greg k-h ^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2020-05-18 7:26 UTC | newest] Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2020-04-20 17:02 [PATCH v3 0/2] Add CTS/RTS gpio support to STM32 UART mani 2020-04-20 17:02 ` [PATCH v3 1/2] dt-bindings: serial: Document CTS/RTS gpios in " mani 2020-05-06 19:59 ` Rob Herring 2020-05-18 7:04 ` Geert Uytterhoeven 2020-05-18 7:25 ` [Linux-stm32] " Erwan LE RAY 2020-04-20 17:02 ` [PATCH v3 2/2] tty: serial: Add modem control gpio support for " mani 2020-04-21 12:58 ` Fabrice Gasnier 2020-05-07 14:07 ` [PATCH v3 0/2] Add CTS/RTS gpio support to " Manivannan Sadhasivam 2020-05-07 15:34 ` Greg KH
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