summaryrefslogtreecommitdiffstats
path: root/kernel/arch/arm/mach-omap2/serial.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/arch/arm/mach-omap2/serial.c')
-rw-r--r--kernel/arch/arm/mach-omap2/serial.c332
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);
+}