Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934927AbcCJCT4 (ORCPT ); Wed, 9 Mar 2016 21:19:56 -0500 Received: from mail.kmu-office.ch ([178.209.48.109]:37384 "EHLO mail.kmu-office.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934839AbcCJCQ4 (ORCPT ); Wed, 9 Mar 2016 21:16:56 -0500 From: Stefan Agner To: shawnguo@kernel.org, mturquette@baylibre.com, sboyd@codeaurora.org Cc: kernel@pengutronix.de, sergeimir@emcraft.com, tglx@linutronix.de, jason@lakedaemon.net, marc.zyngier@arm.com, robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, Stefan Agner Subject: [PATCH 10/18] tty: serial: fsl_lpuart: support suspend/resume Date: Wed, 9 Mar 2016 18:16:51 -0800 Message-Id: <1457576219-7971-11-git-send-email-stefan@agner.ch> X-Mailer: git-send-email 2.7.2 In-Reply-To: <1457576219-7971-1-git-send-email-stefan@agner.ch> References: <1457576219-7971-1-git-send-email-stefan@agner.ch> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3830 Lines: 89 In order to allow wake support in STOP sleep mode, clocks are needed. Use imx_clk_gate2_cgr to disable automatic clock gating in low power mode STOP. This allows to enable wake by UART using: echo enabled > /sys/class/tty/ttyLP0/power/wakeup However, if wake is not enabled, the driver should disable the clocks explicitly to save power. Signed-off-by: Stefan Agner --- drivers/clk/imx/clk-vf610.c | 12 ++++++------ drivers/tty/serial/fsl_lpuart.c | 16 ++++++++++++++-- 2 files changed, 20 insertions(+), 8 deletions(-) diff --git a/drivers/clk/imx/clk-vf610.c b/drivers/clk/imx/clk-vf610.c index e2e2c43..170a96c 100644 --- a/drivers/clk/imx/clk-vf610.c +++ b/drivers/clk/imx/clk-vf610.c @@ -315,12 +315,12 @@ static void __init vf610_clocks_init(struct device_node *ccm_node) clk[VF610_CLK_PIT] = imx_clk_gate2("pit", "ipg_bus", CCM_CCGR1, CCM_CCGRx_CGn(7)); - clk[VF610_CLK_UART0] = imx_clk_gate2("uart0", "ipg_bus", CCM_CCGR0, CCM_CCGRx_CGn(7)); - clk[VF610_CLK_UART1] = imx_clk_gate2("uart1", "ipg_bus", CCM_CCGR0, CCM_CCGRx_CGn(8)); - clk[VF610_CLK_UART2] = imx_clk_gate2("uart2", "ipg_bus", CCM_CCGR0, CCM_CCGRx_CGn(9)); - clk[VF610_CLK_UART3] = imx_clk_gate2("uart3", "ipg_bus", CCM_CCGR0, CCM_CCGRx_CGn(10)); - clk[VF610_CLK_UART4] = imx_clk_gate2("uart4", "ipg_bus", CCM_CCGR6, CCM_CCGRx_CGn(9)); - clk[VF610_CLK_UART5] = imx_clk_gate2("uart5", "ipg_bus", CCM_CCGR6, CCM_CCGRx_CGn(10)); + clk[VF610_CLK_UART0] = imx_clk_gate2_cgr("uart0", "ipg_bus", CCM_CCGR0, CCM_CCGRx_CGn(7), 0x2); + clk[VF610_CLK_UART1] = imx_clk_gate2_cgr("uart1", "ipg_bus", CCM_CCGR0, CCM_CCGRx_CGn(8), 0x2); + clk[VF610_CLK_UART2] = imx_clk_gate2_cgr("uart2", "ipg_bus", CCM_CCGR0, CCM_CCGRx_CGn(9), 0x2); + clk[VF610_CLK_UART3] = imx_clk_gate2_cgr("uart3", "ipg_bus", CCM_CCGR0, CCM_CCGRx_CGn(10), 0x2); + clk[VF610_CLK_UART4] = imx_clk_gate2_cgr("uart4", "ipg_bus", CCM_CCGR6, CCM_CCGRx_CGn(9), 0x2); + clk[VF610_CLK_UART5] = imx_clk_gate2_cgr("uart5", "ipg_bus", CCM_CCGR6, CCM_CCGRx_CGn(10), 0x2); clk[VF610_CLK_I2C0] = imx_clk_gate2("i2c0", "ipg_bus", CCM_CCGR4, CCM_CCGRx_CGn(6)); clk[VF610_CLK_I2C1] = imx_clk_gate2("i2c1", "ipg_bus", CCM_CCGR4, CCM_CCGRx_CGn(7)); diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 3d79003..94e29ba 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -483,9 +483,8 @@ static void lpuart_dma_rx_complete(void *arg) spin_unlock_irqrestore(&sport->port.lock, flags); } -static void lpuart_timer_func(unsigned long data) +static void lpuart_dma_rx_terminate(struct lpuart_port *sport) { - struct lpuart_port *sport = (struct lpuart_port *)data; struct tty_port *port = &sport->port.state->port; struct dma_tx_state state; unsigned long flags; @@ -510,6 +509,11 @@ static void lpuart_timer_func(unsigned long data) spin_unlock_irqrestore(&sport->port.lock, flags); } +static void lpuart_timer_func(unsigned long data) +{ + lpuart_dma_rx_terminate((struct lpuart_port *)data); +} + static inline void lpuart_prepare_rx(struct lpuart_port *sport) { unsigned long flags; @@ -1915,7 +1919,12 @@ static int lpuart_suspend(struct device *dev) writeb(temp, sport->port.membase + UARTCR2); } + if (sport->dma_rx_in_progress) + lpuart_dma_rx_terminate(sport); + uart_suspend_port(&lpuart_reg, &sport->port); + if (sport->port.suspended && !sport->port.irq_wake) + clk_disable_unprepare(sport->clk); return 0; } @@ -1925,6 +1934,9 @@ static int lpuart_resume(struct device *dev) struct lpuart_port *sport = dev_get_drvdata(dev); unsigned long temp; + if (sport->port.suspended && !sport->port.irq_wake) + clk_prepare_enable(sport->clk); + if (sport->lpuart32) { lpuart32_setup_watermark(sport); temp = lpuart32_read(sport->port.membase + UARTCTRL); -- 2.7.2