/*
   * 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;
  	omap_up.DTR_gpio = info->DTR_gpio;
  	omap_up.DTR_inverted = info->DTR_inverted;
  	omap_up.DTR_present = info->DTR_present;
  
  	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.
  ", 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);
  }