From ec3bebc6ec64aac23500e6b8ef5c0aaaeda735cf Mon Sep 17 00:00:00 2001 From: "Govindraj.R" Date: Tue, 11 Oct 2011 19:11:27 +0530 Subject: [PATCH] ARM: OMAP2+: UART: Get context loss count to context restore 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 Acked-by: Greg Kroah-Hartman (for drivers/tty changes) Signed-off-by: Kevin Hilman --- 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 b3f3284bf6ba..78ca7e8fc10b 100644 --- a/arch/arm/mach-omap2/serial.c +++ b/arch/arm/mach-omap2/serial.c @@ -33,6 +33,7 @@ #include #include #include +#include #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 5b913c71cd7f..348c9ead6edb 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 f5a5ed676825..ea4c24aa8c87 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; } -- 2.34.1