Avoid unconditional context restore every time we gate uart clocks. Check whether context loss happened based on which we can context restore uart regs from uart_port structure. Signed-off-by: Govindraj.R <govindraj.raja@xxxxxx> --- arch/arm/mach-omap2/serial.c | 2 ++ arch/arm/plat-omap/include/plat/omap-serial.h | 3 +++ drivers/tty/serial/omap-serial.c | 20 ++++++++++++++++++-- 3 files changed, 23 insertions(+), 2 deletions(-) diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c index 06887d3..98e2666 100644 --- a/arch/arm/mach-omap2/serial.c +++ b/arch/arm/mach-omap2/serial.c @@ -33,6 +33,7 @@ #include <plat/dma.h> #include <plat/omap_hwmod.h> #include <plat/omap_device.h> +#include <plat/omap-pm.h> #include "prm2xxx_3xxx.h" #include "pm.h" @@ -478,6 +479,7 @@ void __init omap_serial_init_port(struct omap_board_data *bdata) omap_up.dma_enabled = uart->dma_enabled; omap_up.uartclk = OMAP24XX_BASE_BAUD * 16; omap_up.flags = UPF_BOOT_AUTOCONF; + omap_up.get_context_loss_count = omap_pm_get_dev_context_loss_count; pdata = &omap_up; pdata_size = sizeof(struct omap_uart_port_info); diff --git a/arch/arm/plat-omap/include/plat/omap-serial.h b/arch/arm/plat-omap/include/plat/omap-serial.h index 5b913c7..348c9ea 100644 --- a/arch/arm/plat-omap/include/plat/omap-serial.h +++ b/arch/arm/plat-omap/include/plat/omap-serial.h @@ -62,6 +62,8 @@ struct omap_uart_port_info { bool dma_enabled; /* To specify DMA Mode */ unsigned int uartclk; /* UART clock rate */ upf_t flags; /* UPF_* flags */ + + int (*get_context_loss_count)(struct device *); }; struct uart_omap_dma { @@ -114,6 +116,7 @@ struct uart_omap_port { unsigned char msr_saved_flags; char name[20]; unsigned long port_activity; + u32 context_loss_cnt; }; #endif /* __OMAP_SERIAL_H__ */ diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index f5a5ed6..ea4c24a 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -1440,15 +1440,31 @@ static void serial_omap_restore_context(struct uart_omap_port *up) #ifdef CONFIG_PM_RUNTIME static int serial_omap_runtime_suspend(struct device *dev) { + struct uart_omap_port *up = dev_get_drvdata(dev); + struct omap_uart_port_info *pdata = dev->platform_data; + + if (!up) + return -EINVAL; + + if (pdata->get_context_loss_count) + up->context_loss_cnt = pdata->get_context_loss_count(dev); + return 0; } static int serial_omap_runtime_resume(struct device *dev) { struct uart_omap_port *up = dev_get_drvdata(dev); + struct omap_uart_port_info *pdata = dev->platform_data; - if (up) - serial_omap_restore_context(up); + if (up) { + if (pdata->get_context_loss_count) { + u32 loss_cnt = pdata->get_context_loss_count(dev); + + if (up->context_loss_cnt != loss_cnt) + serial_omap_restore_context(up); + } + } return 0; } -- 1.7.4.1 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html