From: Govindraj.R Date: Tue, 5 Jun 2012 11:04:11 +0000 (-0700) Subject: OMAP2+: UART: Add mechanism to probe uart pins and configure rx wakeup X-Git-Tag: v3.5-rc4~35^2~3^2~3 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=91930652a23de0873a157aa1d9962cb878d64451;p=karo-tx-linux.git OMAP2+: UART: Add mechanism to probe uart pins and configure rx wakeup The commit (bce492c0 ARM: OMAP2+: UART: Fix incorrect population of default uart pads) removed default uart pads that where getting populated and which was making rx pin wakeup capable. If uart pads were used in different mode by any other module then it would fail since the default pads took over all the uart pins forcefully. With removal of default pads the rx_pad wakeup for console uart while waking up from off mode is broken. Utilise the mux api available to probe the availability of mux pins in uart mode and probe for availability of uart pin in mux mode0 if uart is available as uart pin itself then configure rx pin as wakeup capable. This patch itself doesn't cater to all boards. Boards using uart rx wakeup mechanism should ensure the usage of omap_serial_init_port by configuring required uart ports and pass necessary mux data, till then this probing of uart pins can cater to enabling of rx pad wakeup to most of the boards. This patch can also throw some boot warning from _omap_mux_get_by_name if pin is requested for availability is not present while dynamically probing the uart pins availability such boot warnings can be addressed only when board files are patched with omap_serial_init_port calls passing the right pads needed for a given port. Discussion Threads for reference: http://www.spinics.net/lists/linux-omap/msg69859.html http://www.spinics.net/lists/linux-omap/msg68659.html Cc: Felipe Balbi Cc: Kevin Hilman Cc: Russ Dill Cc: Paul Walmsley Cc: Ameya Palande Signed-off-by: Govindraj.R [tony@atomide.com: updated to fix compile when CONFIG_OMAP_MUX is not set] Signed-off-by: Tony Lindgren --- diff --git a/arch/arm/mach-omap2/mux.c b/arch/arm/mach-omap2/mux.c index 80e55c5c9998..4b46b91cca5c 100644 --- a/arch/arm/mach-omap2/mux.c +++ b/arch/arm/mach-omap2/mux.c @@ -217,8 +217,7 @@ static int __init _omap_mux_get_by_name(struct omap_mux_partition *partition, return -ENODEV; } -static int __init -omap_mux_get_by_name(const char *muxname, +int __init omap_mux_get_by_name(const char *muxname, struct omap_mux_partition **found_partition, struct omap_mux **found_mux) { diff --git a/arch/arm/mach-omap2/mux.h b/arch/arm/mach-omap2/mux.h index 69fe060a0b75..471e62a74a16 100644 --- a/arch/arm/mach-omap2/mux.h +++ b/arch/arm/mach-omap2/mux.h @@ -59,6 +59,7 @@ #define OMAP_PIN_OFF_WAKEUPENABLE OMAP_WAKEUP_EN #define OMAP_MODE_GPIO(x) (((x) & OMAP_MUX_MODE7) == OMAP_MUX_MODE4) +#define OMAP_MODE_UART(x) (((x) & OMAP_MUX_MODE7) == OMAP_MUX_MODE0) /* Flags for omapX_mux_init */ #define OMAP_PACKAGE_MASK 0xffff @@ -225,8 +226,18 @@ omap_hwmod_mux_init(struct omap_device_pad *bpads, int nr_pads); */ void omap_hwmod_mux(struct omap_hwmod_mux_info *hmux, u8 state); +int omap_mux_get_by_name(const char *muxname, + struct omap_mux_partition **found_partition, + struct omap_mux **found_mux); #else +static inline int omap_mux_get_by_name(const char *muxname, + struct omap_mux_partition **found_partition, + struct omap_mux **found_mux) +{ + return 0; +} + static inline int omap_mux_init_gpio(int gpio, int val) { return 0; diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c index 292d4aaca068..c1b93c752d70 100644 --- a/arch/arm/mach-omap2/serial.c +++ b/arch/arm/mach-omap2/serial.c @@ -57,6 +57,7 @@ struct omap_uart_state { struct list_head node; struct omap_hwmod *oh; + struct omap_device_pad default_omap_uart_pads[2]; }; static LIST_HEAD(uart_list); @@ -126,11 +127,70 @@ static void omap_uart_set_smartidle(struct platform_device *pdev) {} #endif /* CONFIG_PM */ #ifdef CONFIG_OMAP_MUX -static void omap_serial_fill_default_pads(struct omap_board_data *bdata) + +#define OMAP_UART_DEFAULT_PAD_NAME_LEN 28 +static char rx_pad_name[OMAP_UART_DEFAULT_PAD_NAME_LEN], + tx_pad_name[OMAP_UART_DEFAULT_PAD_NAME_LEN] __initdata; + +static void __init +omap_serial_fill_uart_tx_rx_pads(struct omap_board_data *bdata, + struct omap_uart_state *uart) +{ + uart->default_omap_uart_pads[0].name = rx_pad_name; + uart->default_omap_uart_pads[0].flags = OMAP_DEVICE_PAD_REMUX | + OMAP_DEVICE_PAD_WAKEUP; + uart->default_omap_uart_pads[0].enable = OMAP_PIN_INPUT | + OMAP_MUX_MODE0; + uart->default_omap_uart_pads[0].idle = OMAP_PIN_INPUT | OMAP_MUX_MODE0; + uart->default_omap_uart_pads[1].name = tx_pad_name; + uart->default_omap_uart_pads[1].enable = OMAP_PIN_OUTPUT | + OMAP_MUX_MODE0; + bdata->pads = uart->default_omap_uart_pads; + bdata->pads_cnt = ARRAY_SIZE(uart->default_omap_uart_pads); +} + +static void __init omap_serial_check_wakeup(struct omap_board_data *bdata, + struct omap_uart_state *uart) { + struct omap_mux_partition *tx_partition = NULL, *rx_partition = NULL; + struct omap_mux *rx_mux = NULL, *tx_mux = NULL; + char *rx_fmt, *tx_fmt; + int uart_nr = bdata->id + 1; + + if (bdata->id != 2) { + rx_fmt = "uart%d_rx.uart%d_rx"; + tx_fmt = "uart%d_tx.uart%d_tx"; + } else { + rx_fmt = "uart%d_rx_irrx.uart%d_rx_irrx"; + tx_fmt = "uart%d_tx_irtx.uart%d_tx_irtx"; + } + + snprintf(rx_pad_name, OMAP_UART_DEFAULT_PAD_NAME_LEN, rx_fmt, + uart_nr, uart_nr); + snprintf(tx_pad_name, OMAP_UART_DEFAULT_PAD_NAME_LEN, tx_fmt, + uart_nr, uart_nr); + + if (omap_mux_get_by_name(rx_pad_name, &rx_partition, &rx_mux) >= 0 && + omap_mux_get_by_name + (tx_pad_name, &tx_partition, &tx_mux) >= 0) { + u16 tx_mode, rx_mode; + + tx_mode = omap_mux_read(tx_partition, tx_mux->reg_offset); + rx_mode = omap_mux_read(rx_partition, rx_mux->reg_offset); + + /* + * Check if uart is used in default tx/rx mode i.e. in mux mode0 + * if yes then configure rx pin for wake up capability + */ + if (OMAP_MODE_UART(rx_mode) && OMAP_MODE_UART(tx_mode)) + omap_serial_fill_uart_tx_rx_pads(bdata, uart); + } } #else -static void omap_serial_fill_default_pads(struct omap_board_data *bdata) {} +static void __init omap_serial_check_wakeup(struct omap_board_data *bdata, + struct omap_uart_state *uart) +{ +} #endif static char *cmdline_find_option(char *str) @@ -287,8 +347,7 @@ void __init omap_serial_board_init(struct omap_uart_port_info *info) bdata.pads = NULL; bdata.pads_cnt = 0; - if (cpu_is_omap44xx() || cpu_is_omap34xx()) - omap_serial_fill_default_pads(&bdata); + omap_serial_check_wakeup(&bdata, uart); if (!info) omap_serial_init_port(&bdata, NULL);