From mboxrd@z Thu Jan 1 00:00:00 1970 From: govindraj.ti@gmail.com (Govindraj) Date: Thu, 5 May 2011 11:25:38 +0530 Subject: [PATCH v2 04/12] Serial: OMAP: Add runtime pm support for omap-serial driver In-Reply-To: <87hb9aqk53.fsf@ti.com> References: <1304080796-625-1-git-send-email-govindraj.raja@ti.com> <1304080796-625-5-git-send-email-govindraj.raja@ti.com> <87hb9aqk53.fsf@ti.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, May 5, 2011 at 2:05 AM, Kevin Hilman wrote: > "Govindraj.R" writes: > >> Adapts omap-serial driver to use pm_runtime api's. >> >> 1.) Populate reg values to uart port which can be used for context restore. >> 2.) Moving context_restore func to driver from serial.c >> 3.) Adding port_enable/disable func to enable/disable given uart port. >> ? ? enable port using get_sync and disable using autosuspend. >> 4.) using runtime irq safe api to make get_sync be called from irq context. >> >> Signed-off-by: Govindraj.R >> --- >> ?arch/arm/mach-omap2/serial.c ? ? ? ? ? ? ? ? ?| ? 16 ++ >> ?arch/arm/plat-omap/include/plat/omap-serial.h | ? ?2 + >> ?drivers/tty/serial/omap-serial.c ? ? ? ? ? ? ?| ?211 ++++++++++++++++++++++--- >> ?3 files changed, 203 insertions(+), 26 deletions(-) >> >> diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c >> index 8c1a4c7..314d82f 100644 >> --- a/arch/arm/mach-omap2/serial.c >> +++ b/arch/arm/mach-omap2/serial.c >> @@ -189,6 +189,21 @@ static void omap_serial_fill_default_pads(struct omap_board_data *bdata) >> ? ? ? } >> ?} >> >> +static void omap_uart_wakeup_enable(struct platform_device *pdev, bool enable) >> +{ >> + ? ? struct omap_uart_port_info *up = pdev->dev.platform_data; >> + >> + ? ? /* Set or clear wake-enable bit */ >> + ? ? if (up->wk_en && up->wk_mask) { >> + ? ? ? ? ? ? u32 v = __raw_readl(up->wk_en); >> + ? ? ? ? ? ? if (enable) >> + ? ? ? ? ? ? ? ? ? ? v |= up->wk_mask; >> + ? ? ? ? ? ? else >> + ? ? ? ? ? ? ? ? ? ? v &= ~up->wk_mask; >> + ? ? ? ? ? ? __raw_writel(v, up->wk_en); >> + ? ? } >> +} > > Rather than having the driver do this via the PRCM, can you do an > experiment? ?Can you try to leave the module-level wakeup enabled all > the time in the PRCM, and the driver can then enable/disable > module-level wakeups simply by toggling ENAWAKEUP in the module's > SYSCONFIG? ?If that works, than you can just use > omap_hwmod_enable_wakeup() for this and not need the above function. > If we leave PRCM uart module level bit enabled all time and we disable wakeup using sysfs echo disabled > /sys/devices/platform/omap/omap_uart.0/power/wakeup it wakes up after clock disable, however unsetting the bit ensures it doesn't wakeup after uart clocks are cut. As Paul suggested, How about adding omap_device/omap_hwmod function to set and unset the bit? Using .module_bit = OMAP3430_EN_UART1_SHIFT, from hwmod data? >> ?static void omap_uart_idle_init(struct omap_uart_port_info *uart, >> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? unsigned short num) >> ?{ >> @@ -332,6 +347,7 @@ void __init omap_serial_init_port(struct omap_board_data *bdata) >> >> ? ? ? pdata->uartclk = OMAP24XX_BASE_BAUD * 16; >> ? ? ? pdata->flags = UPF_BOOT_AUTOCONF; >> + ? ? pdata->enable_wakeup = omap_uart_wakeup_enable; >> ? ? ? if (bdata->id == omap_uart_con_id) >> ? ? ? ? ? ? ? pdata->console_uart = true; <> >> + ? ? pm_runtime_use_autosuspend(&pdev->dev); >> + ? ? pm_runtime_set_autosuspend_delay(&pdev->dev, >> + ? ? ? ? ? ? ? ? ? ? OMAP_UART_AUTOSUSPEND_DELAY); >> + >> + ? ? pm_runtime_enable(&pdev->dev); >> + ? ? pm_runtime_irq_safe(&pdev->dev); >> + >> + ? ? if (omap_up_info->console_uart) { >> + ? ? ? ? ? ? od = to_omap_device(up->pdev); >> + ? ? ? ? ? ? omap_hwmod_idle(od->hwmods[0]); > > Driver should have know knowlege of the underlying hwmod. > > I assume this is here because of the usage of HWMOD_INIT_NO_IDLE and > HWMOD_INIT_NO_RESET, right? Yes correct. >?With proper runtime PM, we should be able to remove the need for using those flags. For omap-uart used for earlyprintk's the early_console driver will use printch from debug macro to print through uart. During omap-hwmod is getting initialized --> _setup --> _idle ---> _disable_clocks at this point of time while printch is happening and hwmod disables uart clocks I dont have uart-console driver available which can enable clocks back. So I have to use those flags when earlyprintk is enabled. -- Thanks, Govindraj.R > > Kevin > >> + ? ? ? ? ? ? serial_omap_port_enable(up); >> + ? ? ? ? ? ? serial_omap_port_disable(up); >> + ? ? } >> + >> ? ? ? ui[pdev->id] = up; >> ? ? ? serial_omap_add_console_port(up); >> >> ? ? ? ret = uart_add_one_port(&serial_omap_reg, &up->port); >> ? ? ? if (ret != 0) >> - ? ? ? ? ? ? goto do_release_region; >> + ? ? ? ? ? ? goto err1; >> >> + ? ? dev_set_drvdata(&pdev->dev, up); >> ? ? ? platform_set_drvdata(pdev, up); >> + >> ? ? ? return 0; >> ?err: >> ? ? ? dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n", >> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? pdev->id, __func__, ret); >> +err1: >> + ? ? kfree(up); >> ?do_release_region: >> ? ? ? release_mem_region(mem->start, (mem->end - mem->start) + 1); >> ? ? ? return ret; >> @@ -1318,20 +1421,76 @@ static int serial_omap_remove(struct platform_device *dev) >> >> ? ? ? platform_set_drvdata(dev, NULL); >> ? ? ? if (up) { >> + ? ? ? ? ? ? pm_runtime_disable(&up->pdev->dev); >> ? ? ? ? ? ? ? uart_remove_one_port(&serial_omap_reg, &up->port); >> ? ? ? ? ? ? ? kfree(up); >> ? ? ? } >> ? ? ? return 0; >> ?} >> >> +static void omap_uart_restore_context(struct uart_omap_port *up) >> +{ >> + ? ? u16 efr = 0; >> + >> + ? ? serial_out(up, UART_OMAP_MDR1, up->mdr1); >> + ? ? serial_out(up, UART_LCR, 0xBF); /* Config B mode */ >> + ? ? efr = serial_in(up, UART_EFR); >> + ? ? serial_out(up, UART_EFR, UART_EFR_ECB); >> + ? ? serial_out(up, UART_LCR, 0x0); /* Operational mode */ >> + ? ? serial_out(up, UART_IER, 0x0); >> + ? ? serial_out(up, UART_LCR, 0xBF); /* Config B mode */ >> + ? ? serial_out(up, UART_DLL, up->dll); >> + ? ? serial_out(up, UART_DLM, up->dlh); >> + ? ? serial_out(up, UART_LCR, 0x0); /* Operational mode */ >> + ? ? serial_out(up, UART_IER, up->ier); >> + ? ? serial_out(up, UART_FCR, up->fcr); >> + ? ? serial_out(up, UART_LCR, 0x80); >> + ? ? serial_out(up, UART_MCR, up->mcr); >> + ? ? serial_out(up, UART_LCR, 0xBF); /* Config B mode */ >> + ? ? serial_out(up, UART_EFR, efr); >> + ? ? serial_out(up, UART_LCR, UART_LCR_WLEN8); >> + ? ? /* UART 16x mode */ >> + ? ? serial_out(up, UART_OMAP_MDR1, up->mdr1); >> +} >> + >> +static int omap_serial_runtime_suspend(struct device *dev) >> +{ >> + ? ? struct uart_omap_port *up = dev_get_drvdata(dev); >> + >> + ? ? if (!up) >> + ? ? ? ? ? ? goto done; >> + >> + ? ? if (device_may_wakeup(dev)) >> + ? ? ? ? ? ? up->enable_wakeup(up->pdev, true); >> + ? ? else >> + ? ? ? ? ? ? up->enable_wakeup(up->pdev, false); >> +done: >> + ? ? return 0; >> +} >> + >> +static int omap_serial_runtime_resume(struct device *dev) >> +{ >> + ? ? struct uart_omap_port *up = dev_get_drvdata(dev); >> + >> + ? ? if (up) >> + ? ? ? ? ? ? omap_uart_restore_context(up); >> + >> + ? ? return 0; >> +} >> + >> +static const struct dev_pm_ops omap_serial_dev_pm_ops = { >> + ? ? .suspend = serial_omap_suspend, >> + ? ? .resume = serial_omap_resume, >> + ? ? .runtime_suspend = omap_serial_runtime_suspend, >> + ? ? .runtime_resume = omap_serial_runtime_resume, >> +}; >> + >> ?static struct platform_driver serial_omap_driver = { >> ? ? ? .probe ? ? ? ? ?= serial_omap_probe, >> ? ? ? .remove ? ? ? ? = serial_omap_remove, >> - >> - ? ? .suspend ? ? ? ?= serial_omap_suspend, >> - ? ? .resume ? ? ? ? = serial_omap_resume, >> ? ? ? .driver ? ? ? ? = { >> ? ? ? ? ? ? ? .name ? = DRIVER_NAME, >> + ? ? ? ? ? ? .pm = &omap_serial_dev_pm_ops, >> ? ? ? }, >> ?}; > -- > To unsubscribe from this list: send the line "unsubscribe linux-serial" in > the body of a message to majordomo at vger.kernel.org > More majordomo info at ?http://vger.kernel.org/majordomo-info.html >