From: Vladimir Murzin <vladimir.murzin@arm.com> To: linux-serial@vger.kernel.org Cc: greg@kroah.com, linux-arm-kernel@lists.infradead.org, sudeep.holla@arm.com Subject: [PATCH v2 1/2] serial: mps2-uart: move to dynamic port allocation Date: Wed, 30 Jan 2019 09:55:14 +0000 [thread overview] Message-ID: <1548842115-14782-2-git-send-email-vladimir.murzin@arm.com> (raw) In-Reply-To: <1548842115-14782-1-git-send-email-vladimir.murzin@arm.com> Some designs, like MPS3, expose number of virtual serial ports which already close or exceeds MPS2_MAX_PORTS. Increasing MPS2_MAX_PORTS would have negative impact (in terms of memory consumption) on tiny MPS2 platform which, in fact, has only one physically populated UART. Start with converting existent static port array to idr. As a bonus it make driver not to fail in case when no alias was specified in device tree. Note: there is no need in idr_destroy() because code doesn't unload since ce87122911f8 ("serial: mps2-uart: make driver explicitly non-modular") Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> --- Changelog v1 -> v2 - added a note about idr_destroy() drivers/tty/serial/mps2-uart.c | 47 ++++++++++++++++++++++++++++-------------- 1 file changed, 31 insertions(+), 16 deletions(-) diff --git a/drivers/tty/serial/mps2-uart.c b/drivers/tty/serial/mps2-uart.c index 9f8f637..6da0633 100644 --- a/drivers/tty/serial/mps2-uart.c +++ b/drivers/tty/serial/mps2-uart.c @@ -22,6 +22,7 @@ #include <linux/serial_core.h> #include <linux/tty_flip.h> #include <linux/types.h> +#include <linux/idr.h> #define SERIAL_NAME "ttyMPS" #define DRIVER_NAME "mps2-uart" @@ -397,7 +398,7 @@ static const struct uart_ops mps2_uart_pops = { .verify_port = mps2_uart_verify_port, }; -static struct mps2_uart_port mps2_uart_ports[MPS2_MAX_PORTS]; +static DEFINE_IDR(ports_idr); #ifdef CONFIG_SERIAL_MPS2_UART_CONSOLE static void mps2_uart_console_putchar(struct uart_port *port, int ch) @@ -410,7 +411,8 @@ static void mps2_uart_console_putchar(struct uart_port *port, int ch) static void mps2_uart_console_write(struct console *co, const char *s, unsigned int cnt) { - struct uart_port *port = &mps2_uart_ports[co->index].port; + struct mps2_uart_port *mps_port = idr_find(&ports_idr, co->index); + struct uart_port *port = &mps_port->port; uart_console_write(port, s, cnt, mps2_uart_console_putchar); } @@ -426,7 +428,10 @@ static int mps2_uart_console_setup(struct console *co, char *options) if (co->index < 0 || co->index >= MPS2_MAX_PORTS) return -ENODEV; - mps_port = &mps2_uart_ports[co->index]; + mps_port = idr_find(&ports_idr, co->index); + + if (!mps_port) + return -ENODEV; if (options) uart_parse_options(options, &baud, &parity, &bits, &flow); @@ -487,27 +492,32 @@ static struct uart_driver mps2_uart_driver = { .cons = MPS2_SERIAL_CONSOLE, }; -static struct mps2_uart_port *mps2_of_get_port(struct platform_device *pdev) +static int mps2_of_get_port(struct platform_device *pdev, + struct mps2_uart_port *mps_port) { struct device_node *np = pdev->dev.of_node; int id; if (!np) - return NULL; + return -ENODEV; id = of_alias_get_id(np, "serial"); + + if (id < 0) + id = idr_alloc_cyclic(&ports_idr, (void *)mps_port, 0, MPS2_MAX_PORTS, GFP_KERNEL); + else + id = idr_alloc(&ports_idr, (void *)mps_port, id, MPS2_MAX_PORTS, GFP_KERNEL); + if (id < 0) - id = 0; + return id; - if (WARN_ON(id >= MPS2_MAX_PORTS)) - return NULL; + mps_port->port.line = id; - mps2_uart_ports[id].port.line = id; - return &mps2_uart_ports[id]; + return 0; } -static int mps2_init_port(struct mps2_uart_port *mps_port, - struct platform_device *pdev) +static int mps2_init_port(struct platform_device *pdev, + struct mps2_uart_port *mps_port) { struct resource *res; int ret; @@ -550,11 +560,16 @@ static int mps2_serial_probe(struct platform_device *pdev) struct mps2_uart_port *mps_port; int ret; - mps_port = mps2_of_get_port(pdev); - if (!mps_port) - return -ENODEV; + mps_port = devm_kzalloc(&pdev->dev, sizeof(struct mps2_uart_port), GFP_KERNEL); + + if (!mps_port) + return -ENOMEM; + + ret = mps2_of_get_port(pdev, mps_port); + if (ret) + return ret; - ret = mps2_init_port(mps_port, pdev); + ret = mps2_init_port(pdev, mps_port); if (ret) return ret; -- 2.7.4
WARNING: multiple messages have this Message-ID (diff)
From: Vladimir Murzin <vladimir.murzin@arm.com> To: linux-serial@vger.kernel.org Cc: greg@kroah.com, linux-arm-kernel@lists.infradead.org, sudeep.holla@arm.com Subject: [PATCH v2 1/2] serial: mps2-uart: move to dynamic port allocation Date: Wed, 30 Jan 2019 09:55:14 +0000 [thread overview] Message-ID: <1548842115-14782-2-git-send-email-vladimir.murzin@arm.com> (raw) In-Reply-To: <1548842115-14782-1-git-send-email-vladimir.murzin@arm.com> Some designs, like MPS3, expose number of virtual serial ports which already close or exceeds MPS2_MAX_PORTS. Increasing MPS2_MAX_PORTS would have negative impact (in terms of memory consumption) on tiny MPS2 platform which, in fact, has only one physically populated UART. Start with converting existent static port array to idr. As a bonus it make driver not to fail in case when no alias was specified in device tree. Note: there is no need in idr_destroy() because code doesn't unload since ce87122911f8 ("serial: mps2-uart: make driver explicitly non-modular") Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> --- Changelog v1 -> v2 - added a note about idr_destroy() drivers/tty/serial/mps2-uart.c | 47 ++++++++++++++++++++++++++++-------------- 1 file changed, 31 insertions(+), 16 deletions(-) diff --git a/drivers/tty/serial/mps2-uart.c b/drivers/tty/serial/mps2-uart.c index 9f8f637..6da0633 100644 --- a/drivers/tty/serial/mps2-uart.c +++ b/drivers/tty/serial/mps2-uart.c @@ -22,6 +22,7 @@ #include <linux/serial_core.h> #include <linux/tty_flip.h> #include <linux/types.h> +#include <linux/idr.h> #define SERIAL_NAME "ttyMPS" #define DRIVER_NAME "mps2-uart" @@ -397,7 +398,7 @@ static const struct uart_ops mps2_uart_pops = { .verify_port = mps2_uart_verify_port, }; -static struct mps2_uart_port mps2_uart_ports[MPS2_MAX_PORTS]; +static DEFINE_IDR(ports_idr); #ifdef CONFIG_SERIAL_MPS2_UART_CONSOLE static void mps2_uart_console_putchar(struct uart_port *port, int ch) @@ -410,7 +411,8 @@ static void mps2_uart_console_putchar(struct uart_port *port, int ch) static void mps2_uart_console_write(struct console *co, const char *s, unsigned int cnt) { - struct uart_port *port = &mps2_uart_ports[co->index].port; + struct mps2_uart_port *mps_port = idr_find(&ports_idr, co->index); + struct uart_port *port = &mps_port->port; uart_console_write(port, s, cnt, mps2_uart_console_putchar); } @@ -426,7 +428,10 @@ static int mps2_uart_console_setup(struct console *co, char *options) if (co->index < 0 || co->index >= MPS2_MAX_PORTS) return -ENODEV; - mps_port = &mps2_uart_ports[co->index]; + mps_port = idr_find(&ports_idr, co->index); + + if (!mps_port) + return -ENODEV; if (options) uart_parse_options(options, &baud, &parity, &bits, &flow); @@ -487,27 +492,32 @@ static struct uart_driver mps2_uart_driver = { .cons = MPS2_SERIAL_CONSOLE, }; -static struct mps2_uart_port *mps2_of_get_port(struct platform_device *pdev) +static int mps2_of_get_port(struct platform_device *pdev, + struct mps2_uart_port *mps_port) { struct device_node *np = pdev->dev.of_node; int id; if (!np) - return NULL; + return -ENODEV; id = of_alias_get_id(np, "serial"); + + if (id < 0) + id = idr_alloc_cyclic(&ports_idr, (void *)mps_port, 0, MPS2_MAX_PORTS, GFP_KERNEL); + else + id = idr_alloc(&ports_idr, (void *)mps_port, id, MPS2_MAX_PORTS, GFP_KERNEL); + if (id < 0) - id = 0; + return id; - if (WARN_ON(id >= MPS2_MAX_PORTS)) - return NULL; + mps_port->port.line = id; - mps2_uart_ports[id].port.line = id; - return &mps2_uart_ports[id]; + return 0; } -static int mps2_init_port(struct mps2_uart_port *mps_port, - struct platform_device *pdev) +static int mps2_init_port(struct platform_device *pdev, + struct mps2_uart_port *mps_port) { struct resource *res; int ret; @@ -550,11 +560,16 @@ static int mps2_serial_probe(struct platform_device *pdev) struct mps2_uart_port *mps_port; int ret; - mps_port = mps2_of_get_port(pdev); - if (!mps_port) - return -ENODEV; + mps_port = devm_kzalloc(&pdev->dev, sizeof(struct mps2_uart_port), GFP_KERNEL); + + if (!mps_port) + return -ENOMEM; + + ret = mps2_of_get_port(pdev, mps_port); + if (ret) + return ret; - ret = mps2_init_port(mps_port, pdev); + ret = mps2_init_port(pdev, mps_port); if (ret) return ret; -- 2.7.4 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-01-30 9:55 UTC|newest] Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top 2019-01-30 9:55 [PATCH v2 0/2] serial: mps2-uart: minor improvements Vladimir Murzin 2019-01-30 9:55 ` Vladimir Murzin 2019-01-30 9:55 ` Vladimir Murzin [this message] 2019-01-30 9:55 ` [PATCH v2 1/2] serial: mps2-uart: move to dynamic port allocation Vladimir Murzin 2019-01-30 9:55 ` [PATCH v2 2/2] serial: mps2-uart: support combined irq Vladimir Murzin 2019-01-30 9:55 ` Vladimir Murzin
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