From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicolas Ferre Subject: Re: [PATCH 4/8] tty: atmel_serial: prepare clk before calling enable Date: Thu, 20 Jun 2013 12:20:35 +0200 Message-ID: <51C2D773.7010402@atmel.com> References: <1371640263-9268-1-git-send-email-b.brezillon@overkiz.com> <1371640650-9625-1-git-send-email-b.brezillon@overkiz.com> <51C2B3D1.9060601@atmel.com> <51C2B814.4050308@overkiz.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from eusmtp01.atmel.com ([212.144.249.242]:42976 "EHLO eusmtp01.atmel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964966Ab3FTKUn (ORCPT ); Thu, 20 Jun 2013 06:20:43 -0400 In-Reply-To: <51C2B814.4050308@overkiz.com> Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: boris brezillon Cc: Ludovic Desroches , Jean-Christophe Plagniol-Villard , Greg Kroah-Hartman , Jiri Slaby , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org On 20/06/2013 10:06, boris brezillon : > On 20/06/2013 09:48, Nicolas Ferre wrote: >> On 19/06/2013 13:17, Boris BREZILLON : >>> Replace clk_enable/disable with clk_prepare_enable/disable_unprepare to >>> avoid common clk framework warnings. >>> >>> Signed-off-by: Boris BREZILLON >> >> Acked-by: Nicolas Ferre >> >> (one comment though) >> >>> --- >>> drivers/tty/serial/atmel_serial.c | 41 >>> ++++++++++++++++++++++++++++--------- >>> 1 file changed, 31 insertions(+), 10 deletions(-) >>> >>> diff --git a/drivers/tty/serial/atmel_serial.c >>> b/drivers/tty/serial/atmel_serial.c >>> index 3467462..691265f 100644 >>> --- a/drivers/tty/serial/atmel_serial.c >>> +++ b/drivers/tty/serial/atmel_serial.c >>> @@ -1100,7 +1100,7 @@ static void atmel_serial_pm(struct uart_port >>> *port, unsigned int state, >>> * Enable the peripheral clock for this serial port. >>> * This is called on uart_open() or a resume event. >>> */ >>> - clk_enable(atmel_port->clk); >>> + clk_prepare_enable(atmel_port->clk); >> >> Do we need to check return code here? > We could, but the pm function will not reflect the failure (void return). > In addition, the clk_prepare_enable should not fail because it already > succeed in the probe > function (no memory allocation, simple bit masking in clk-peripheral > implem). > > I can add it add this check (and avoid the interrrupt activation if it > fails) if you want. No, it seems okay like that. Thanks for the precision. Bye, > >> >>> >>> /* re-enable interrupts if we disabled some on suspend */ >>> UART_PUT_IER(port, atmel_port->backup_imr); >>> @@ -1114,7 +1114,7 @@ static void atmel_serial_pm(struct uart_port >>> *port, unsigned int state, >>> * Disable the peripheral clock for this serial port. >>> * This is called on uart_close() or a suspend event. >>> */ >>> - clk_disable(atmel_port->clk); >>> + clk_disable_unprepare(atmel_port->clk); >>> break; >>> default: >>> printk(KERN_ERR "atmel_serial: unknown pm %d\n", state); >>> @@ -1458,9 +1458,10 @@ static void atmel_of_init_port(struct >>> atmel_uart_port *atmel_port, >>> /* >>> * Configure the port from the platform device resource info. >>> */ >>> -static void atmel_init_port(struct atmel_uart_port *atmel_port, >>> +static int atmel_init_port(struct atmel_uart_port *atmel_port, >>> struct platform_device *pdev) >>> { >>> + int ret; >>> struct uart_port *port = &atmel_port->uart; >>> struct atmel_uart_data *pdata = pdev->dev.platform_data; >>> >>> @@ -1496,9 +1497,19 @@ static void atmel_init_port(struct >>> atmel_uart_port *atmel_port, >>> /* for console, the clock could already be configured */ >>> if (!atmel_port->clk) { >>> atmel_port->clk = clk_get(&pdev->dev, "usart"); >>> - clk_enable(atmel_port->clk); >>> + if (IS_ERR(atmel_port->clk)) { >>> + ret = PTR_ERR(atmel_port->clk); >>> + atmel_port->clk = NULL; >>> + return ret; >>> + } >>> + ret = clk_prepare_enable(atmel_port->clk); >>> + if (ret) { >>> + clk_put(atmel_port->clk); >>> + atmel_port->clk = NULL; >>> + return ret; >>> + } >>> port->uartclk = clk_get_rate(atmel_port->clk); >>> - clk_disable(atmel_port->clk); >>> + clk_disable_unprepare(atmel_port->clk); >>> /* only enable clock when USART is in use */ >>> } >>> >>> @@ -1511,6 +1522,8 @@ static void atmel_init_port(struct >>> atmel_uart_port *atmel_port, >>> } else { >>> atmel_port->tx_done_mask = ATMEL_US_TXRDY; >>> } >>> + >>> + return 0; >>> } >>> >>> struct platform_device *atmel_default_console_device; /* the >>> serial console device */ >>> @@ -1601,6 +1614,7 @@ static void __init >>> atmel_console_get_options(struct uart_port *port, int *baud, >>> >>> static int __init atmel_console_setup(struct console *co, char >>> *options) >>> { >>> + int ret; >>> struct uart_port *port = &atmel_ports[co->index].uart; >>> int baud = 115200; >>> int bits = 8; >>> @@ -1612,7 +1626,9 @@ static int __init atmel_console_setup(struct >>> console *co, char *options) >>> return -ENODEV; >>> } >>> >>> - clk_enable(atmel_ports[co->index].clk); >>> + ret = clk_prepare_enable(atmel_ports[co->index].clk); >>> + if (ret) >>> + return ret; >>> >>> UART_PUT_IDR(port, -1); >>> UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX); >>> @@ -1645,6 +1661,7 @@ static struct console atmel_console = { >>> */ >>> static int __init atmel_console_init(void) >>> { >>> + int ret; >>> if (atmel_default_console_device) { >>> struct atmel_uart_data *pdata = >>> atmel_default_console_device->dev.platform_data; >>> @@ -1655,7 +1672,9 @@ static int __init atmel_console_init(void) >>> port->uart.line = id; >>> >>> add_preferred_console(ATMEL_DEVICENAME, id, NULL); >>> - atmel_init_port(port, atmel_default_console_device); >>> + ret = atmel_init_port(port, atmel_default_console_device); >>> + if (ret) >>> + return ret; >>> register_console(&atmel_console); >>> } >>> >>> @@ -1786,7 +1805,9 @@ static int atmel_serial_probe(struct >>> platform_device *pdev) >>> port->backup_imr = 0; >>> port->uart.line = ret; >>> >>> - atmel_init_port(port, pdev); >>> + ret = atmel_init_port(port, pdev); >>> + if (ret) >>> + goto err; >>> >>> pinctrl = devm_pinctrl_get_select_default(&pdev->dev); >>> if (IS_ERR(pinctrl)) { >>> @@ -1812,9 +1833,9 @@ static int atmel_serial_probe(struct >>> platform_device *pdev) >>> && ATMEL_CONSOLE_DEVICE->flags & CON_ENABLED) { >>> /* >>> * The serial core enabled the clock for us, so undo >>> - * the clk_enable() in atmel_console_setup() >>> + * the clk_prepare_enable() in atmel_console_setup() >>> */ >>> - clk_disable(port->clk); >>> + clk_disable_unprepare(port->clk); >>> } >>> #endif >>> >>> >> >> > > > -- Nicolas Ferre From mboxrd@z Thu Jan 1 00:00:00 1970 From: nicolas.ferre@atmel.com (Nicolas Ferre) Date: Thu, 20 Jun 2013 12:20:35 +0200 Subject: [PATCH 4/8] tty: atmel_serial: prepare clk before calling enable In-Reply-To: <51C2B814.4050308@overkiz.com> References: <1371640263-9268-1-git-send-email-b.brezillon@overkiz.com> <1371640650-9625-1-git-send-email-b.brezillon@overkiz.com> <51C2B3D1.9060601@atmel.com> <51C2B814.4050308@overkiz.com> Message-ID: <51C2D773.7010402@atmel.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 20/06/2013 10:06, boris brezillon : > On 20/06/2013 09:48, Nicolas Ferre wrote: >> On 19/06/2013 13:17, Boris BREZILLON : >>> Replace clk_enable/disable with clk_prepare_enable/disable_unprepare to >>> avoid common clk framework warnings. >>> >>> Signed-off-by: Boris BREZILLON >> >> Acked-by: Nicolas Ferre >> >> (one comment though) >> >>> --- >>> drivers/tty/serial/atmel_serial.c | 41 >>> ++++++++++++++++++++++++++++--------- >>> 1 file changed, 31 insertions(+), 10 deletions(-) >>> >>> diff --git a/drivers/tty/serial/atmel_serial.c >>> b/drivers/tty/serial/atmel_serial.c >>> index 3467462..691265f 100644 >>> --- a/drivers/tty/serial/atmel_serial.c >>> +++ b/drivers/tty/serial/atmel_serial.c >>> @@ -1100,7 +1100,7 @@ static void atmel_serial_pm(struct uart_port >>> *port, unsigned int state, >>> * Enable the peripheral clock for this serial port. >>> * This is called on uart_open() or a resume event. >>> */ >>> - clk_enable(atmel_port->clk); >>> + clk_prepare_enable(atmel_port->clk); >> >> Do we need to check return code here? > We could, but the pm function will not reflect the failure (void return). > In addition, the clk_prepare_enable should not fail because it already > succeed in the probe > function (no memory allocation, simple bit masking in clk-peripheral > implem). > > I can add it add this check (and avoid the interrrupt activation if it > fails) if you want. No, it seems okay like that. Thanks for the precision. Bye, > >> >>> >>> /* re-enable interrupts if we disabled some on suspend */ >>> UART_PUT_IER(port, atmel_port->backup_imr); >>> @@ -1114,7 +1114,7 @@ static void atmel_serial_pm(struct uart_port >>> *port, unsigned int state, >>> * Disable the peripheral clock for this serial port. >>> * This is called on uart_close() or a suspend event. >>> */ >>> - clk_disable(atmel_port->clk); >>> + clk_disable_unprepare(atmel_port->clk); >>> break; >>> default: >>> printk(KERN_ERR "atmel_serial: unknown pm %d\n", state); >>> @@ -1458,9 +1458,10 @@ static void atmel_of_init_port(struct >>> atmel_uart_port *atmel_port, >>> /* >>> * Configure the port from the platform device resource info. >>> */ >>> -static void atmel_init_port(struct atmel_uart_port *atmel_port, >>> +static int atmel_init_port(struct atmel_uart_port *atmel_port, >>> struct platform_device *pdev) >>> { >>> + int ret; >>> struct uart_port *port = &atmel_port->uart; >>> struct atmel_uart_data *pdata = pdev->dev.platform_data; >>> >>> @@ -1496,9 +1497,19 @@ static void atmel_init_port(struct >>> atmel_uart_port *atmel_port, >>> /* for console, the clock could already be configured */ >>> if (!atmel_port->clk) { >>> atmel_port->clk = clk_get(&pdev->dev, "usart"); >>> - clk_enable(atmel_port->clk); >>> + if (IS_ERR(atmel_port->clk)) { >>> + ret = PTR_ERR(atmel_port->clk); >>> + atmel_port->clk = NULL; >>> + return ret; >>> + } >>> + ret = clk_prepare_enable(atmel_port->clk); >>> + if (ret) { >>> + clk_put(atmel_port->clk); >>> + atmel_port->clk = NULL; >>> + return ret; >>> + } >>> port->uartclk = clk_get_rate(atmel_port->clk); >>> - clk_disable(atmel_port->clk); >>> + clk_disable_unprepare(atmel_port->clk); >>> /* only enable clock when USART is in use */ >>> } >>> >>> @@ -1511,6 +1522,8 @@ static void atmel_init_port(struct >>> atmel_uart_port *atmel_port, >>> } else { >>> atmel_port->tx_done_mask = ATMEL_US_TXRDY; >>> } >>> + >>> + return 0; >>> } >>> >>> struct platform_device *atmel_default_console_device; /* the >>> serial console device */ >>> @@ -1601,6 +1614,7 @@ static void __init >>> atmel_console_get_options(struct uart_port *port, int *baud, >>> >>> static int __init atmel_console_setup(struct console *co, char >>> *options) >>> { >>> + int ret; >>> struct uart_port *port = &atmel_ports[co->index].uart; >>> int baud = 115200; >>> int bits = 8; >>> @@ -1612,7 +1626,9 @@ static int __init atmel_console_setup(struct >>> console *co, char *options) >>> return -ENODEV; >>> } >>> >>> - clk_enable(atmel_ports[co->index].clk); >>> + ret = clk_prepare_enable(atmel_ports[co->index].clk); >>> + if (ret) >>> + return ret; >>> >>> UART_PUT_IDR(port, -1); >>> UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX); >>> @@ -1645,6 +1661,7 @@ static struct console atmel_console = { >>> */ >>> static int __init atmel_console_init(void) >>> { >>> + int ret; >>> if (atmel_default_console_device) { >>> struct atmel_uart_data *pdata = >>> atmel_default_console_device->dev.platform_data; >>> @@ -1655,7 +1672,9 @@ static int __init atmel_console_init(void) >>> port->uart.line = id; >>> >>> add_preferred_console(ATMEL_DEVICENAME, id, NULL); >>> - atmel_init_port(port, atmel_default_console_device); >>> + ret = atmel_init_port(port, atmel_default_console_device); >>> + if (ret) >>> + return ret; >>> register_console(&atmel_console); >>> } >>> >>> @@ -1786,7 +1805,9 @@ static int atmel_serial_probe(struct >>> platform_device *pdev) >>> port->backup_imr = 0; >>> port->uart.line = ret; >>> >>> - atmel_init_port(port, pdev); >>> + ret = atmel_init_port(port, pdev); >>> + if (ret) >>> + goto err; >>> >>> pinctrl = devm_pinctrl_get_select_default(&pdev->dev); >>> if (IS_ERR(pinctrl)) { >>> @@ -1812,9 +1833,9 @@ static int atmel_serial_probe(struct >>> platform_device *pdev) >>> && ATMEL_CONSOLE_DEVICE->flags & CON_ENABLED) { >>> /* >>> * The serial core enabled the clock for us, so undo >>> - * the clk_enable() in atmel_console_setup() >>> + * the clk_prepare_enable() in atmel_console_setup() >>> */ >>> - clk_disable(port->clk); >>> + clk_disable_unprepare(port->clk); >>> } >>> #endif >>> >>> >> >> > > > -- Nicolas Ferre From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965299Ab3FTKUq (ORCPT ); Thu, 20 Jun 2013 06:20:46 -0400 Received: from eusmtp01.atmel.com ([212.144.249.242]:42976 "EHLO eusmtp01.atmel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964966Ab3FTKUn (ORCPT ); Thu, 20 Jun 2013 06:20:43 -0400 Message-ID: <51C2D773.7010402@atmel.com> Date: Thu, 20 Jun 2013 12:20:35 +0200 From: Nicolas Ferre Organization: atmel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130510 Thunderbird/17.0.6 MIME-Version: 1.0 To: boris brezillon CC: Ludovic Desroches , "Jean-Christophe Plagniol-Villard" , Greg Kroah-Hartman , Jiri Slaby , , , Subject: Re: [PATCH 4/8] tty: atmel_serial: prepare clk before calling enable References: <1371640263-9268-1-git-send-email-b.brezillon@overkiz.com> <1371640650-9625-1-git-send-email-b.brezillon@overkiz.com> <51C2B3D1.9060601@atmel.com> <51C2B814.4050308@overkiz.com> In-Reply-To: <51C2B814.4050308@overkiz.com> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.161.30.18] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 20/06/2013 10:06, boris brezillon : > On 20/06/2013 09:48, Nicolas Ferre wrote: >> On 19/06/2013 13:17, Boris BREZILLON : >>> Replace clk_enable/disable with clk_prepare_enable/disable_unprepare to >>> avoid common clk framework warnings. >>> >>> Signed-off-by: Boris BREZILLON >> >> Acked-by: Nicolas Ferre >> >> (one comment though) >> >>> --- >>> drivers/tty/serial/atmel_serial.c | 41 >>> ++++++++++++++++++++++++++++--------- >>> 1 file changed, 31 insertions(+), 10 deletions(-) >>> >>> diff --git a/drivers/tty/serial/atmel_serial.c >>> b/drivers/tty/serial/atmel_serial.c >>> index 3467462..691265f 100644 >>> --- a/drivers/tty/serial/atmel_serial.c >>> +++ b/drivers/tty/serial/atmel_serial.c >>> @@ -1100,7 +1100,7 @@ static void atmel_serial_pm(struct uart_port >>> *port, unsigned int state, >>> * Enable the peripheral clock for this serial port. >>> * This is called on uart_open() or a resume event. >>> */ >>> - clk_enable(atmel_port->clk); >>> + clk_prepare_enable(atmel_port->clk); >> >> Do we need to check return code here? > We could, but the pm function will not reflect the failure (void return). > In addition, the clk_prepare_enable should not fail because it already > succeed in the probe > function (no memory allocation, simple bit masking in clk-peripheral > implem). > > I can add it add this check (and avoid the interrrupt activation if it > fails) if you want. No, it seems okay like that. Thanks for the precision. Bye, > >> >>> >>> /* re-enable interrupts if we disabled some on suspend */ >>> UART_PUT_IER(port, atmel_port->backup_imr); >>> @@ -1114,7 +1114,7 @@ static void atmel_serial_pm(struct uart_port >>> *port, unsigned int state, >>> * Disable the peripheral clock for this serial port. >>> * This is called on uart_close() or a suspend event. >>> */ >>> - clk_disable(atmel_port->clk); >>> + clk_disable_unprepare(atmel_port->clk); >>> break; >>> default: >>> printk(KERN_ERR "atmel_serial: unknown pm %d\n", state); >>> @@ -1458,9 +1458,10 @@ static void atmel_of_init_port(struct >>> atmel_uart_port *atmel_port, >>> /* >>> * Configure the port from the platform device resource info. >>> */ >>> -static void atmel_init_port(struct atmel_uart_port *atmel_port, >>> +static int atmel_init_port(struct atmel_uart_port *atmel_port, >>> struct platform_device *pdev) >>> { >>> + int ret; >>> struct uart_port *port = &atmel_port->uart; >>> struct atmel_uart_data *pdata = pdev->dev.platform_data; >>> >>> @@ -1496,9 +1497,19 @@ static void atmel_init_port(struct >>> atmel_uart_port *atmel_port, >>> /* for console, the clock could already be configured */ >>> if (!atmel_port->clk) { >>> atmel_port->clk = clk_get(&pdev->dev, "usart"); >>> - clk_enable(atmel_port->clk); >>> + if (IS_ERR(atmel_port->clk)) { >>> + ret = PTR_ERR(atmel_port->clk); >>> + atmel_port->clk = NULL; >>> + return ret; >>> + } >>> + ret = clk_prepare_enable(atmel_port->clk); >>> + if (ret) { >>> + clk_put(atmel_port->clk); >>> + atmel_port->clk = NULL; >>> + return ret; >>> + } >>> port->uartclk = clk_get_rate(atmel_port->clk); >>> - clk_disable(atmel_port->clk); >>> + clk_disable_unprepare(atmel_port->clk); >>> /* only enable clock when USART is in use */ >>> } >>> >>> @@ -1511,6 +1522,8 @@ static void atmel_init_port(struct >>> atmel_uart_port *atmel_port, >>> } else { >>> atmel_port->tx_done_mask = ATMEL_US_TXRDY; >>> } >>> + >>> + return 0; >>> } >>> >>> struct platform_device *atmel_default_console_device; /* the >>> serial console device */ >>> @@ -1601,6 +1614,7 @@ static void __init >>> atmel_console_get_options(struct uart_port *port, int *baud, >>> >>> static int __init atmel_console_setup(struct console *co, char >>> *options) >>> { >>> + int ret; >>> struct uart_port *port = &atmel_ports[co->index].uart; >>> int baud = 115200; >>> int bits = 8; >>> @@ -1612,7 +1626,9 @@ static int __init atmel_console_setup(struct >>> console *co, char *options) >>> return -ENODEV; >>> } >>> >>> - clk_enable(atmel_ports[co->index].clk); >>> + ret = clk_prepare_enable(atmel_ports[co->index].clk); >>> + if (ret) >>> + return ret; >>> >>> UART_PUT_IDR(port, -1); >>> UART_PUT_CR(port, ATMEL_US_RSTSTA | ATMEL_US_RSTRX); >>> @@ -1645,6 +1661,7 @@ static struct console atmel_console = { >>> */ >>> static int __init atmel_console_init(void) >>> { >>> + int ret; >>> if (atmel_default_console_device) { >>> struct atmel_uart_data *pdata = >>> atmel_default_console_device->dev.platform_data; >>> @@ -1655,7 +1672,9 @@ static int __init atmel_console_init(void) >>> port->uart.line = id; >>> >>> add_preferred_console(ATMEL_DEVICENAME, id, NULL); >>> - atmel_init_port(port, atmel_default_console_device); >>> + ret = atmel_init_port(port, atmel_default_console_device); >>> + if (ret) >>> + return ret; >>> register_console(&atmel_console); >>> } >>> >>> @@ -1786,7 +1805,9 @@ static int atmel_serial_probe(struct >>> platform_device *pdev) >>> port->backup_imr = 0; >>> port->uart.line = ret; >>> >>> - atmel_init_port(port, pdev); >>> + ret = atmel_init_port(port, pdev); >>> + if (ret) >>> + goto err; >>> >>> pinctrl = devm_pinctrl_get_select_default(&pdev->dev); >>> if (IS_ERR(pinctrl)) { >>> @@ -1812,9 +1833,9 @@ static int atmel_serial_probe(struct >>> platform_device *pdev) >>> && ATMEL_CONSOLE_DEVICE->flags & CON_ENABLED) { >>> /* >>> * The serial core enabled the clock for us, so undo >>> - * the clk_enable() in atmel_console_setup() >>> + * the clk_prepare_enable() in atmel_console_setup() >>> */ >>> - clk_disable(port->clk); >>> + clk_disable_unprepare(port->clk); >>> } >>> #endif >>> >>> >> >> > > > -- Nicolas Ferre