diff options
Diffstat (limited to 'kernel/arch/arm/mach-omap2/serial.c')
| -rw-r--r-- | kernel/arch/arm/mach-omap2/serial.c | 332 |
1 files changed, 332 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-omap2/serial.c b/kernel/arch/arm/mach-omap2/serial.c new file mode 100644 index 000000000..57dee0c7c --- /dev/null +++ b/kernel/arch/arm/mach-omap2/serial.c @@ -0,0 +1,332 @@ +/* + * arch/arm/mach-omap2/serial.c + * + * OMAP2 serial support. + * + * Copyright (C) 2005-2008 Nokia Corporation + * Author: Paul Mundt <paul.mundt@nokia.com> + * + * Major rework for PM support by Kevin Hilman + * + * Based off of arch/arm/mach-omap/omap1/serial.c + * + * Copyright (C) 2009 Texas Instruments + * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/delay.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/pm_runtime.h> +#include <linux/console.h> +#include <linux/omap-dma.h> +#include <linux/platform_data/serial-omap.h> + +#include "common.h" +#include "omap_hwmod.h" +#include "omap_device.h" +#include "omap-pm.h" +#include "soc.h" +#include "prm2xxx_3xxx.h" +#include "pm.h" +#include "cm2xxx_3xxx.h" +#include "prm-regbits-34xx.h" +#include "control.h" +#include "mux.h" +#include "serial.h" + +/* + * NOTE: By default the serial auto_suspend timeout is disabled as it causes + * lost characters over the serial ports. This means that the UART clocks will + * stay on until power/autosuspend_delay is set for the uart from sysfs. + * This also causes that any deeper omap sleep states are blocked. + */ +#define DEFAULT_AUTOSUSPEND_DELAY -1 + +#define MAX_UART_HWMOD_NAME_LEN 16 + +struct omap_uart_state { + int num; + + struct list_head node; + struct omap_hwmod *oh; + struct omap_device_pad default_omap_uart_pads[2]; +}; + +static LIST_HEAD(uart_list); +static u8 num_uarts; +static u8 console_uart_id = -1; +static u8 uart_debug; + +#define DEFAULT_RXDMA_POLLRATE 1 /* RX DMA polling rate (us) */ +#define DEFAULT_RXDMA_BUFSIZE 4096 /* RX DMA buffer size */ +#define DEFAULT_RXDMA_TIMEOUT (3 * HZ)/* RX DMA timeout (jiffies) */ + +static struct omap_uart_port_info omap_serial_default_info[] __initdata = { + { + .dma_enabled = false, + .dma_rx_buf_size = DEFAULT_RXDMA_BUFSIZE, + .dma_rx_poll_rate = DEFAULT_RXDMA_POLLRATE, + .dma_rx_timeout = DEFAULT_RXDMA_TIMEOUT, + .autosuspend_timeout = DEFAULT_AUTOSUSPEND_DELAY, + }, +}; + +#ifdef CONFIG_PM +static void omap_uart_enable_wakeup(struct device *dev, bool enable) +{ + struct platform_device *pdev = to_platform_device(dev); + struct omap_device *od = to_omap_device(pdev); + + if (!od) + return; + + if (enable) + omap_hwmod_enable_wakeup(od->hwmods[0]); + else + omap_hwmod_disable_wakeup(od->hwmods[0]); +} + +#else +static void omap_uart_enable_wakeup(struct device *dev, bool enable) +{} +#endif /* CONFIG_PM */ + +#ifdef CONFIG_OMAP_MUX + +#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 __init omap_serial_check_wakeup(struct omap_board_data *bdata, + struct omap_uart_state *uart) +{ +} +#endif + +static char *cmdline_find_option(char *str) +{ + extern char *saved_command_line; + + return strstr(saved_command_line, str); +} + +static int __init omap_serial_early_init(void) +{ + if (of_have_populated_dt()) + return -ENODEV; + + do { + char oh_name[MAX_UART_HWMOD_NAME_LEN]; + struct omap_hwmod *oh; + struct omap_uart_state *uart; + char uart_name[MAX_UART_HWMOD_NAME_LEN]; + + snprintf(oh_name, MAX_UART_HWMOD_NAME_LEN, + "uart%d", num_uarts + 1); + oh = omap_hwmod_lookup(oh_name); + if (!oh) + break; + + uart = kzalloc(sizeof(struct omap_uart_state), GFP_KERNEL); + if (WARN_ON(!uart)) + return -ENODEV; + + uart->oh = oh; + uart->num = num_uarts++; + list_add_tail(&uart->node, &uart_list); + snprintf(uart_name, MAX_UART_HWMOD_NAME_LEN, + "%s%d", OMAP_SERIAL_NAME, uart->num); + + if (cmdline_find_option(uart_name)) { + console_uart_id = uart->num; + + if (console_loglevel >= 10) { + uart_debug = true; + pr_info("%s used as console in debug mode: uart%d clocks will not be gated", + uart_name, uart->num); + } + } + } while (1); + + return 0; +} +omap_core_initcall(omap_serial_early_init); + +/** + * omap_serial_init_port() - initialize single serial port + * @bdata: port specific board data pointer + * @info: platform specific data pointer + * + * This function initialies serial driver for given port only. + * Platforms can call this function instead of omap_serial_init() + * if they don't plan to use all available UARTs as serial ports. + * + * Don't mix calls to omap_serial_init_port() and omap_serial_init(), + * use only one of the two. + */ +void __init omap_serial_init_port(struct omap_board_data *bdata, + struct omap_uart_port_info *info) +{ + struct omap_uart_state *uart; + struct omap_hwmod *oh; + struct platform_device *pdev; + void *pdata = NULL; + u32 pdata_size = 0; + char *name; + struct omap_uart_port_info omap_up; + + if (WARN_ON(!bdata)) + return; + if (WARN_ON(bdata->id < 0)) + return; + if (WARN_ON(bdata->id >= num_uarts)) + return; + + list_for_each_entry(uart, &uart_list, node) + if (bdata->id == uart->num) + break; + if (!info) + info = omap_serial_default_info; + + oh = uart->oh; + name = DRIVER_NAME; + + omap_up.dma_enabled = info->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; + omap_up.enable_wakeup = omap_uart_enable_wakeup; + omap_up.dma_rx_buf_size = info->dma_rx_buf_size; + omap_up.dma_rx_timeout = info->dma_rx_timeout; + omap_up.dma_rx_poll_rate = info->dma_rx_poll_rate; + omap_up.autosuspend_timeout = info->autosuspend_timeout; + + pdata = &omap_up; + pdata_size = sizeof(struct omap_uart_port_info); + + if (WARN_ON(!oh)) + return; + + pdev = omap_device_build(name, uart->num, oh, pdata, pdata_size); + if (IS_ERR(pdev)) { + WARN(1, "Could not build omap_device for %s: %s.\n", name, + oh->name); + return; + } + + oh->mux = omap_hwmod_mux_init(bdata->pads, bdata->pads_cnt); + + if (console_uart_id == bdata->id) { + omap_device_enable(pdev); + pm_runtime_set_active(&pdev->dev); + } + + oh->dev_attr = uart; + + if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads) + && !uart_debug) + device_init_wakeup(&pdev->dev, true); +} + +/** + * omap_serial_board_init() - initialize all supported serial ports + * @info: platform specific data pointer + * + * Initializes all available UARTs as serial ports. Platforms + * can call this function when they want to have default behaviour + * for serial ports (e.g initialize them all as serial ports). + */ +void __init omap_serial_board_init(struct omap_uart_port_info *info) +{ + struct omap_uart_state *uart; + struct omap_board_data bdata; + + list_for_each_entry(uart, &uart_list, node) { + bdata.id = uart->num; + bdata.flags = 0; + bdata.pads = NULL; + bdata.pads_cnt = 0; + + omap_serial_check_wakeup(&bdata, uart); + + if (!info) + omap_serial_init_port(&bdata, NULL); + else + omap_serial_init_port(&bdata, &info[uart->num]); + } +} + +/** + * omap_serial_init() - initialize all supported serial ports + * + * Initializes all available UARTs. + * Platforms can call this function when they want to have default behaviour + * for serial ports (e.g initialize them all as serial ports). + */ +void __init omap_serial_init(void) +{ + omap_serial_board_init(NULL); +} |