|  | /* | 
|  | * 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/serial_reg.h> | 
|  | #include <linux/clk.h> | 
|  | #include <linux/io.h> | 
|  | #include <linux/delay.h> | 
|  | #include <linux/platform_device.h> | 
|  | #include <linux/slab.h> | 
|  | #include <linux/serial_8250.h> | 
|  | #include <linux/pm_runtime.h> | 
|  | #include <linux/console.h> | 
|  |  | 
|  | #ifdef CONFIG_SERIAL_OMAP | 
|  | #include <plat/omap-serial.h> | 
|  | #endif | 
|  |  | 
|  | #include <plat/common.h> | 
|  | #include <plat/board.h> | 
|  | #include <plat/clock.h> | 
|  | #include <plat/dma.h> | 
|  | #include <plat/omap_hwmod.h> | 
|  | #include <plat/omap_device.h> | 
|  |  | 
|  | #include "prm2xxx_3xxx.h" | 
|  | #include "pm.h" | 
|  | #include "cm2xxx_3xxx.h" | 
|  | #include "prm-regbits-34xx.h" | 
|  | #include "control.h" | 
|  | #include "mux.h" | 
|  |  | 
|  | #define UART_OMAP_NO_EMPTY_FIFO_READ_IP_REV	0x52 | 
|  | #define UART_OMAP_WER		0x17	/* Wake-up enable register */ | 
|  |  | 
|  | #define UART_ERRATA_FIFO_FULL_ABORT	(0x1 << 0) | 
|  | #define UART_ERRATA_i202_MDR1_ACCESS	(0x1 << 1) | 
|  |  | 
|  | /* | 
|  | * NOTE: By default the serial timeout is disabled as it causes lost characters | 
|  | * over the serial ports. This means that the UART clocks will stay on until | 
|  | * disabled via sysfs. This also causes that any deeper omap sleep states are | 
|  | * blocked. | 
|  | */ | 
|  | #define DEFAULT_TIMEOUT 0 | 
|  |  | 
|  | #define MAX_UART_HWMOD_NAME_LEN		16 | 
|  |  | 
|  | struct omap_uart_state { | 
|  | int num; | 
|  | int can_sleep; | 
|  | struct timer_list timer; | 
|  | u32 timeout; | 
|  |  | 
|  | void __iomem *wk_st; | 
|  | void __iomem *wk_en; | 
|  | u32 wk_mask; | 
|  | u32 padconf; | 
|  | u32 dma_enabled; | 
|  |  | 
|  | struct clk *ick; | 
|  | struct clk *fck; | 
|  | int clocked; | 
|  |  | 
|  | int irq; | 
|  | int regshift; | 
|  | int irqflags; | 
|  | void __iomem *membase; | 
|  | resource_size_t mapbase; | 
|  |  | 
|  | struct list_head node; | 
|  | struct omap_hwmod *oh; | 
|  | struct platform_device *pdev; | 
|  |  | 
|  | u32 errata; | 
|  | #if defined(CONFIG_ARCH_OMAP3) && defined(CONFIG_PM) | 
|  | int context_valid; | 
|  |  | 
|  | /* Registers to be saved/restored for OFF-mode */ | 
|  | u16 dll; | 
|  | u16 dlh; | 
|  | u16 ier; | 
|  | u16 sysc; | 
|  | u16 scr; | 
|  | u16 wer; | 
|  | u16 mcr; | 
|  | #endif | 
|  | }; | 
|  |  | 
|  | static LIST_HEAD(uart_list); | 
|  | static u8 num_uarts; | 
|  |  | 
|  | static inline unsigned int __serial_read_reg(struct uart_port *up, | 
|  | int offset) | 
|  | { | 
|  | offset <<= up->regshift; | 
|  | return (unsigned int)__raw_readb(up->membase + offset); | 
|  | } | 
|  |  | 
|  | static inline unsigned int serial_read_reg(struct omap_uart_state *uart, | 
|  | int offset) | 
|  | { | 
|  | offset <<= uart->regshift; | 
|  | return (unsigned int)__raw_readb(uart->membase + offset); | 
|  | } | 
|  |  | 
|  | static inline void __serial_write_reg(struct uart_port *up, int offset, | 
|  | int value) | 
|  | { | 
|  | offset <<= up->regshift; | 
|  | __raw_writeb(value, up->membase + offset); | 
|  | } | 
|  |  | 
|  | static inline void serial_write_reg(struct omap_uart_state *uart, int offset, | 
|  | int value) | 
|  | { | 
|  | offset <<= uart->regshift; | 
|  | __raw_writeb(value, uart->membase + offset); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Internal UARTs need to be initialized for the 8250 autoconfig to work | 
|  | * properly. Note that the TX watermark initialization may not be needed | 
|  | * once the 8250.c watermark handling code is merged. | 
|  | */ | 
|  |  | 
|  | static inline void __init omap_uart_reset(struct omap_uart_state *uart) | 
|  | { | 
|  | serial_write_reg(uart, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE); | 
|  | serial_write_reg(uart, UART_OMAP_SCR, 0x08); | 
|  | serial_write_reg(uart, UART_OMAP_MDR1, UART_OMAP_MDR1_16X_MODE); | 
|  | } | 
|  |  | 
|  | #if defined(CONFIG_PM) && defined(CONFIG_ARCH_OMAP3) | 
|  |  | 
|  | /* | 
|  | * Work Around for Errata i202 (3430 - 1.12, 3630 - 1.6) | 
|  | * The access to uart register after MDR1 Access | 
|  | * causes UART to corrupt data. | 
|  | * | 
|  | * Need a delay = | 
|  | * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS) | 
|  | * give 10 times as much | 
|  | */ | 
|  | static void omap_uart_mdr1_errataset(struct omap_uart_state *uart, u8 mdr1_val, | 
|  | u8 fcr_val) | 
|  | { | 
|  | u8 timeout = 255; | 
|  |  | 
|  | serial_write_reg(uart, UART_OMAP_MDR1, mdr1_val); | 
|  | udelay(2); | 
|  | serial_write_reg(uart, UART_FCR, fcr_val | UART_FCR_CLEAR_XMIT | | 
|  | UART_FCR_CLEAR_RCVR); | 
|  | /* | 
|  | * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and | 
|  | * TX_FIFO_E bit is 1. | 
|  | */ | 
|  | while (UART_LSR_THRE != (serial_read_reg(uart, UART_LSR) & | 
|  | (UART_LSR_THRE | UART_LSR_DR))) { | 
|  | timeout--; | 
|  | if (!timeout) { | 
|  | /* Should *never* happen. we warn and carry on */ | 
|  | dev_crit(&uart->pdev->dev, "Errata i202: timedout %x\n", | 
|  | serial_read_reg(uart, UART_LSR)); | 
|  | break; | 
|  | } | 
|  | udelay(1); | 
|  | } | 
|  | } | 
|  |  | 
|  | static void omap_uart_save_context(struct omap_uart_state *uart) | 
|  | { | 
|  | u16 lcr = 0; | 
|  |  | 
|  | if (!enable_off_mode) | 
|  | return; | 
|  |  | 
|  | lcr = serial_read_reg(uart, UART_LCR); | 
|  | serial_write_reg(uart, UART_LCR, UART_LCR_CONF_MODE_B); | 
|  | uart->dll = serial_read_reg(uart, UART_DLL); | 
|  | uart->dlh = serial_read_reg(uart, UART_DLM); | 
|  | serial_write_reg(uart, UART_LCR, lcr); | 
|  | uart->ier = serial_read_reg(uart, UART_IER); | 
|  | uart->sysc = serial_read_reg(uart, UART_OMAP_SYSC); | 
|  | uart->scr = serial_read_reg(uart, UART_OMAP_SCR); | 
|  | uart->wer = serial_read_reg(uart, UART_OMAP_WER); | 
|  | serial_write_reg(uart, UART_LCR, UART_LCR_CONF_MODE_A); | 
|  | uart->mcr = serial_read_reg(uart, UART_MCR); | 
|  | serial_write_reg(uart, UART_LCR, lcr); | 
|  |  | 
|  | uart->context_valid = 1; | 
|  | } | 
|  |  | 
|  | static void omap_uart_restore_context(struct omap_uart_state *uart) | 
|  | { | 
|  | u16 efr = 0; | 
|  |  | 
|  | if (!enable_off_mode) | 
|  | return; | 
|  |  | 
|  | if (!uart->context_valid) | 
|  | return; | 
|  |  | 
|  | uart->context_valid = 0; | 
|  |  | 
|  | if (uart->errata & UART_ERRATA_i202_MDR1_ACCESS) | 
|  | omap_uart_mdr1_errataset(uart, UART_OMAP_MDR1_DISABLE, 0xA0); | 
|  | else | 
|  | serial_write_reg(uart, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE); | 
|  |  | 
|  | serial_write_reg(uart, UART_LCR, UART_LCR_CONF_MODE_B); | 
|  | efr = serial_read_reg(uart, UART_EFR); | 
|  | serial_write_reg(uart, UART_EFR, UART_EFR_ECB); | 
|  | serial_write_reg(uart, UART_LCR, 0x0); /* Operational mode */ | 
|  | serial_write_reg(uart, UART_IER, 0x0); | 
|  | serial_write_reg(uart, UART_LCR, UART_LCR_CONF_MODE_B); | 
|  | serial_write_reg(uart, UART_DLL, uart->dll); | 
|  | serial_write_reg(uart, UART_DLM, uart->dlh); | 
|  | serial_write_reg(uart, UART_LCR, 0x0); /* Operational mode */ | 
|  | serial_write_reg(uart, UART_IER, uart->ier); | 
|  | serial_write_reg(uart, UART_LCR, UART_LCR_CONF_MODE_A); | 
|  | serial_write_reg(uart, UART_MCR, uart->mcr); | 
|  | serial_write_reg(uart, UART_LCR, UART_LCR_CONF_MODE_B); | 
|  | serial_write_reg(uart, UART_EFR, efr); | 
|  | serial_write_reg(uart, UART_LCR, UART_LCR_WLEN8); | 
|  | serial_write_reg(uart, UART_OMAP_SCR, uart->scr); | 
|  | serial_write_reg(uart, UART_OMAP_WER, uart->wer); | 
|  | serial_write_reg(uart, UART_OMAP_SYSC, uart->sysc); | 
|  |  | 
|  | if (uart->errata & UART_ERRATA_i202_MDR1_ACCESS) | 
|  | omap_uart_mdr1_errataset(uart, UART_OMAP_MDR1_16X_MODE, 0xA1); | 
|  | else | 
|  | /* UART 16x mode */ | 
|  | serial_write_reg(uart, UART_OMAP_MDR1, | 
|  | UART_OMAP_MDR1_16X_MODE); | 
|  | } | 
|  | #else | 
|  | static inline void omap_uart_save_context(struct omap_uart_state *uart) {} | 
|  | static inline void omap_uart_restore_context(struct omap_uart_state *uart) {} | 
|  | #endif /* CONFIG_PM && CONFIG_ARCH_OMAP3 */ | 
|  |  | 
|  | static inline void omap_uart_enable_clocks(struct omap_uart_state *uart) | 
|  | { | 
|  | if (uart->clocked) | 
|  | return; | 
|  |  | 
|  | omap_device_enable(uart->pdev); | 
|  | uart->clocked = 1; | 
|  | omap_uart_restore_context(uart); | 
|  | } | 
|  |  | 
|  | #ifdef CONFIG_PM | 
|  |  | 
|  | static inline void omap_uart_disable_clocks(struct omap_uart_state *uart) | 
|  | { | 
|  | if (!uart->clocked) | 
|  | return; | 
|  |  | 
|  | omap_uart_save_context(uart); | 
|  | uart->clocked = 0; | 
|  | omap_device_idle(uart->pdev); | 
|  | } | 
|  |  | 
|  | static void omap_uart_enable_wakeup(struct omap_uart_state *uart) | 
|  | { | 
|  | /* Set wake-enable bit */ | 
|  | if (uart->wk_en && uart->wk_mask) { | 
|  | u32 v = __raw_readl(uart->wk_en); | 
|  | v |= uart->wk_mask; | 
|  | __raw_writel(v, uart->wk_en); | 
|  | } | 
|  |  | 
|  | /* Ensure IOPAD wake-enables are set */ | 
|  | if (cpu_is_omap34xx() && uart->padconf) { | 
|  | u16 v = omap_ctrl_readw(uart->padconf); | 
|  | v |= OMAP3_PADCONF_WAKEUPENABLE0; | 
|  | omap_ctrl_writew(v, uart->padconf); | 
|  | } | 
|  | } | 
|  |  | 
|  | static void omap_uart_disable_wakeup(struct omap_uart_state *uart) | 
|  | { | 
|  | /* Clear wake-enable bit */ | 
|  | if (uart->wk_en && uart->wk_mask) { | 
|  | u32 v = __raw_readl(uart->wk_en); | 
|  | v &= ~uart->wk_mask; | 
|  | __raw_writel(v, uart->wk_en); | 
|  | } | 
|  |  | 
|  | /* Ensure IOPAD wake-enables are cleared */ | 
|  | if (cpu_is_omap34xx() && uart->padconf) { | 
|  | u16 v = omap_ctrl_readw(uart->padconf); | 
|  | v &= ~OMAP3_PADCONF_WAKEUPENABLE0; | 
|  | omap_ctrl_writew(v, uart->padconf); | 
|  | } | 
|  | } | 
|  |  | 
|  | static void omap_uart_smart_idle_enable(struct omap_uart_state *uart, | 
|  | int enable) | 
|  | { | 
|  | u8 idlemode; | 
|  |  | 
|  | if (enable) { | 
|  | /** | 
|  | * Errata 2.15: [UART]:Cannot Acknowledge Idle Requests | 
|  | * in Smartidle Mode When Configured for DMA Operations. | 
|  | */ | 
|  | if (uart->dma_enabled) | 
|  | idlemode = HWMOD_IDLEMODE_FORCE; | 
|  | else | 
|  | idlemode = HWMOD_IDLEMODE_SMART; | 
|  | } else { | 
|  | idlemode = HWMOD_IDLEMODE_NO; | 
|  | } | 
|  |  | 
|  | omap_hwmod_set_slave_idlemode(uart->oh, idlemode); | 
|  | } | 
|  |  | 
|  | static void omap_uart_block_sleep(struct omap_uart_state *uart) | 
|  | { | 
|  | omap_uart_enable_clocks(uart); | 
|  |  | 
|  | omap_uart_smart_idle_enable(uart, 0); | 
|  | uart->can_sleep = 0; | 
|  | if (uart->timeout) | 
|  | mod_timer(&uart->timer, jiffies + uart->timeout); | 
|  | else | 
|  | del_timer(&uart->timer); | 
|  | } | 
|  |  | 
|  | static void omap_uart_allow_sleep(struct omap_uart_state *uart) | 
|  | { | 
|  | if (device_may_wakeup(&uart->pdev->dev)) | 
|  | omap_uart_enable_wakeup(uart); | 
|  | else | 
|  | omap_uart_disable_wakeup(uart); | 
|  |  | 
|  | if (!uart->clocked) | 
|  | return; | 
|  |  | 
|  | omap_uart_smart_idle_enable(uart, 1); | 
|  | uart->can_sleep = 1; | 
|  | del_timer(&uart->timer); | 
|  | } | 
|  |  | 
|  | static void omap_uart_idle_timer(unsigned long data) | 
|  | { | 
|  | struct omap_uart_state *uart = (struct omap_uart_state *)data; | 
|  |  | 
|  | omap_uart_allow_sleep(uart); | 
|  | } | 
|  |  | 
|  | void omap_uart_prepare_idle(int num) | 
|  | { | 
|  | struct omap_uart_state *uart; | 
|  |  | 
|  | list_for_each_entry(uart, &uart_list, node) { | 
|  | if (num == uart->num && uart->can_sleep) { | 
|  | omap_uart_disable_clocks(uart); | 
|  | return; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | void omap_uart_resume_idle(int num) | 
|  | { | 
|  | struct omap_uart_state *uart; | 
|  |  | 
|  | list_for_each_entry(uart, &uart_list, node) { | 
|  | if (num == uart->num && uart->can_sleep) { | 
|  | omap_uart_enable_clocks(uart); | 
|  |  | 
|  | /* Check for IO pad wakeup */ | 
|  | if (cpu_is_omap34xx() && uart->padconf) { | 
|  | u16 p = omap_ctrl_readw(uart->padconf); | 
|  |  | 
|  | if (p & OMAP3_PADCONF_WAKEUPEVENT0) | 
|  | omap_uart_block_sleep(uart); | 
|  | } | 
|  |  | 
|  | /* Check for normal UART wakeup */ | 
|  | if (__raw_readl(uart->wk_st) & uart->wk_mask) | 
|  | omap_uart_block_sleep(uart); | 
|  | return; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | void omap_uart_prepare_suspend(void) | 
|  | { | 
|  | struct omap_uart_state *uart; | 
|  |  | 
|  | list_for_each_entry(uart, &uart_list, node) { | 
|  | omap_uart_allow_sleep(uart); | 
|  | } | 
|  | } | 
|  |  | 
|  | int omap_uart_can_sleep(void) | 
|  | { | 
|  | struct omap_uart_state *uart; | 
|  | int can_sleep = 1; | 
|  |  | 
|  | list_for_each_entry(uart, &uart_list, node) { | 
|  | if (!uart->clocked) | 
|  | continue; | 
|  |  | 
|  | if (!uart->can_sleep) { | 
|  | can_sleep = 0; | 
|  | continue; | 
|  | } | 
|  |  | 
|  | /* This UART can now safely sleep. */ | 
|  | omap_uart_allow_sleep(uart); | 
|  | } | 
|  |  | 
|  | return can_sleep; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * omap_uart_interrupt() | 
|  | * | 
|  | * This handler is used only to detect that *any* UART interrupt has | 
|  | * occurred.  It does _nothing_ to handle the interrupt.  Rather, | 
|  | * any UART interrupt will trigger the inactivity timer so the | 
|  | * UART will not idle or sleep for its timeout period. | 
|  | * | 
|  | **/ | 
|  | /* static int first_interrupt; */ | 
|  | static irqreturn_t omap_uart_interrupt(int irq, void *dev_id) | 
|  | { | 
|  | struct omap_uart_state *uart = dev_id; | 
|  |  | 
|  | omap_uart_block_sleep(uart); | 
|  |  | 
|  | return IRQ_NONE; | 
|  | } | 
|  |  | 
|  | static void omap_uart_idle_init(struct omap_uart_state *uart) | 
|  | { | 
|  | int ret; | 
|  |  | 
|  | uart->can_sleep = 0; | 
|  | uart->timeout = DEFAULT_TIMEOUT; | 
|  | setup_timer(&uart->timer, omap_uart_idle_timer, | 
|  | (unsigned long) uart); | 
|  | if (uart->timeout) | 
|  | mod_timer(&uart->timer, jiffies + uart->timeout); | 
|  | omap_uart_smart_idle_enable(uart, 0); | 
|  |  | 
|  | if (cpu_is_omap34xx() && !cpu_is_ti816x()) { | 
|  | u32 mod = (uart->num > 1) ? OMAP3430_PER_MOD : CORE_MOD; | 
|  | u32 wk_mask = 0; | 
|  | u32 padconf = 0; | 
|  |  | 
|  | /* XXX These PRM accesses do not belong here */ | 
|  | uart->wk_en = OMAP34XX_PRM_REGADDR(mod, PM_WKEN1); | 
|  | uart->wk_st = OMAP34XX_PRM_REGADDR(mod, PM_WKST1); | 
|  | switch (uart->num) { | 
|  | case 0: | 
|  | wk_mask = OMAP3430_ST_UART1_MASK; | 
|  | padconf = 0x182; | 
|  | break; | 
|  | case 1: | 
|  | wk_mask = OMAP3430_ST_UART2_MASK; | 
|  | padconf = 0x17a; | 
|  | break; | 
|  | case 2: | 
|  | wk_mask = OMAP3430_ST_UART3_MASK; | 
|  | padconf = 0x19e; | 
|  | break; | 
|  | case 3: | 
|  | wk_mask = OMAP3630_ST_UART4_MASK; | 
|  | padconf = 0x0d2; | 
|  | break; | 
|  | } | 
|  | uart->wk_mask = wk_mask; | 
|  | uart->padconf = padconf; | 
|  | } else if (cpu_is_omap24xx()) { | 
|  | u32 wk_mask = 0; | 
|  | u32 wk_en = PM_WKEN1, wk_st = PM_WKST1; | 
|  |  | 
|  | switch (uart->num) { | 
|  | case 0: | 
|  | wk_mask = OMAP24XX_ST_UART1_MASK; | 
|  | break; | 
|  | case 1: | 
|  | wk_mask = OMAP24XX_ST_UART2_MASK; | 
|  | break; | 
|  | case 2: | 
|  | wk_en = OMAP24XX_PM_WKEN2; | 
|  | wk_st = OMAP24XX_PM_WKST2; | 
|  | wk_mask = OMAP24XX_ST_UART3_MASK; | 
|  | break; | 
|  | } | 
|  | uart->wk_mask = wk_mask; | 
|  | if (cpu_is_omap2430()) { | 
|  | uart->wk_en = OMAP2430_PRM_REGADDR(CORE_MOD, wk_en); | 
|  | uart->wk_st = OMAP2430_PRM_REGADDR(CORE_MOD, wk_st); | 
|  | } else if (cpu_is_omap2420()) { | 
|  | uart->wk_en = OMAP2420_PRM_REGADDR(CORE_MOD, wk_en); | 
|  | uart->wk_st = OMAP2420_PRM_REGADDR(CORE_MOD, wk_st); | 
|  | } | 
|  | } else { | 
|  | uart->wk_en = NULL; | 
|  | uart->wk_st = NULL; | 
|  | uart->wk_mask = 0; | 
|  | uart->padconf = 0; | 
|  | } | 
|  |  | 
|  | uart->irqflags |= IRQF_SHARED; | 
|  | ret = request_threaded_irq(uart->irq, NULL, omap_uart_interrupt, | 
|  | IRQF_SHARED, "serial idle", (void *)uart); | 
|  | WARN_ON(ret); | 
|  | } | 
|  |  | 
|  | void omap_uart_enable_irqs(int enable) | 
|  | { | 
|  | int ret; | 
|  | struct omap_uart_state *uart; | 
|  |  | 
|  | list_for_each_entry(uart, &uart_list, node) { | 
|  | if (enable) { | 
|  | pm_runtime_put_sync(&uart->pdev->dev); | 
|  | ret = request_threaded_irq(uart->irq, NULL, | 
|  | omap_uart_interrupt, | 
|  | IRQF_SHARED, | 
|  | "serial idle", | 
|  | (void *)uart); | 
|  | } else { | 
|  | pm_runtime_get_noresume(&uart->pdev->dev); | 
|  | free_irq(uart->irq, (void *)uart); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | static ssize_t sleep_timeout_show(struct device *dev, | 
|  | struct device_attribute *attr, | 
|  | char *buf) | 
|  | { | 
|  | struct platform_device *pdev = to_platform_device(dev); | 
|  | struct omap_device *odev = to_omap_device(pdev); | 
|  | struct omap_uart_state *uart = odev->hwmods[0]->dev_attr; | 
|  |  | 
|  | return sprintf(buf, "%u\n", uart->timeout / HZ); | 
|  | } | 
|  |  | 
|  | static ssize_t sleep_timeout_store(struct device *dev, | 
|  | struct device_attribute *attr, | 
|  | const char *buf, size_t n) | 
|  | { | 
|  | struct platform_device *pdev = to_platform_device(dev); | 
|  | struct omap_device *odev = to_omap_device(pdev); | 
|  | struct omap_uart_state *uart = odev->hwmods[0]->dev_attr; | 
|  | unsigned int value; | 
|  |  | 
|  | if (sscanf(buf, "%u", &value) != 1) { | 
|  | dev_err(dev, "sleep_timeout_store: Invalid value\n"); | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | uart->timeout = value * HZ; | 
|  | if (uart->timeout) | 
|  | mod_timer(&uart->timer, jiffies + uart->timeout); | 
|  | else | 
|  | /* A zero value means disable timeout feature */ | 
|  | omap_uart_block_sleep(uart); | 
|  |  | 
|  | return n; | 
|  | } | 
|  |  | 
|  | static DEVICE_ATTR(sleep_timeout, 0644, sleep_timeout_show, | 
|  | sleep_timeout_store); | 
|  | #define DEV_CREATE_FILE(dev, attr) WARN_ON(device_create_file(dev, attr)) | 
|  | #else | 
|  | static inline void omap_uart_idle_init(struct omap_uart_state *uart) {} | 
|  | static void omap_uart_block_sleep(struct omap_uart_state *uart) | 
|  | { | 
|  | /* Needed to enable UART clocks when built without CONFIG_PM */ | 
|  | omap_uart_enable_clocks(uart); | 
|  | } | 
|  | #define DEV_CREATE_FILE(dev, attr) | 
|  | #endif /* CONFIG_PM */ | 
|  |  | 
|  | #ifndef CONFIG_SERIAL_OMAP | 
|  | /* | 
|  | * Override the default 8250 read handler: mem_serial_in() | 
|  | * Empty RX fifo read causes an abort on omap3630 and omap4 | 
|  | * This function makes sure that an empty rx fifo is not read on these silicons | 
|  | * (OMAP1/2/3430 are not affected) | 
|  | */ | 
|  | static unsigned int serial_in_override(struct uart_port *up, int offset) | 
|  | { | 
|  | if (UART_RX == offset) { | 
|  | unsigned int lsr; | 
|  | lsr = __serial_read_reg(up, UART_LSR); | 
|  | if (!(lsr & UART_LSR_DR)) | 
|  | return -EPERM; | 
|  | } | 
|  |  | 
|  | return __serial_read_reg(up, offset); | 
|  | } | 
|  |  | 
|  | static void serial_out_override(struct uart_port *up, int offset, int value) | 
|  | { | 
|  | unsigned int status, tmout = 10000; | 
|  |  | 
|  | status = __serial_read_reg(up, UART_LSR); | 
|  | while (!(status & UART_LSR_THRE)) { | 
|  | /* Wait up to 10ms for the character(s) to be sent. */ | 
|  | if (--tmout == 0) | 
|  | break; | 
|  | udelay(1); | 
|  | status = __serial_read_reg(up, UART_LSR); | 
|  | } | 
|  | __serial_write_reg(up, offset, value); | 
|  | } | 
|  | #endif | 
|  |  | 
|  | static int __init omap_serial_early_init(void) | 
|  | { | 
|  | int i = 0; | 
|  |  | 
|  | do { | 
|  | char oh_name[MAX_UART_HWMOD_NAME_LEN]; | 
|  | struct omap_hwmod *oh; | 
|  | struct omap_uart_state *uart; | 
|  |  | 
|  | snprintf(oh_name, MAX_UART_HWMOD_NAME_LEN, | 
|  | "uart%d", i + 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 = i++; | 
|  | list_add_tail(&uart->node, &uart_list); | 
|  | num_uarts++; | 
|  |  | 
|  | /* | 
|  | * NOTE: omap_hwmod_setup*() has not yet been called, | 
|  | *       so no hwmod functions will work yet. | 
|  | */ | 
|  |  | 
|  | /* | 
|  | * During UART early init, device need to be probed | 
|  | * to determine SoC specific init before omap_device | 
|  | * is ready.  Therefore, don't allow idle here | 
|  | */ | 
|  | uart->oh->flags |= HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET; | 
|  | } while (1); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  | core_initcall(omap_serial_early_init); | 
|  |  | 
|  | /** | 
|  | * omap_serial_init_port() - initialize single serial port | 
|  | * @bdata: port specific board 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_state *uart; | 
|  | struct omap_hwmod *oh; | 
|  | struct platform_device *pdev; | 
|  | void *pdata = NULL; | 
|  | u32 pdata_size = 0; | 
|  | char *name; | 
|  | #ifndef CONFIG_SERIAL_OMAP | 
|  | struct plat_serial8250_port ports[2] = { | 
|  | {}, | 
|  | {.flags = 0}, | 
|  | }; | 
|  | struct plat_serial8250_port *p = &ports[0]; | 
|  | #else | 
|  | struct omap_uart_port_info omap_up; | 
|  | #endif | 
|  |  | 
|  | 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; | 
|  |  | 
|  | oh = uart->oh; | 
|  | uart->dma_enabled = 0; | 
|  | #ifndef CONFIG_SERIAL_OMAP | 
|  | name = "serial8250"; | 
|  |  | 
|  | /* | 
|  | * !! 8250 driver does not use standard IORESOURCE* It | 
|  | * has it's own custom pdata that can be taken from | 
|  | * the hwmod resource data.  But, this needs to be | 
|  | * done after the build. | 
|  | * | 
|  | * ?? does it have to be done before the register ?? | 
|  | * YES, because platform_device_data_add() copies | 
|  | * pdata, it does not use a pointer. | 
|  | */ | 
|  | p->flags = UPF_BOOT_AUTOCONF; | 
|  | p->iotype = UPIO_MEM; | 
|  | p->regshift = 2; | 
|  | p->uartclk = OMAP24XX_BASE_BAUD * 16; | 
|  | p->irq = oh->mpu_irqs[0].irq; | 
|  | p->mapbase = oh->slaves[0]->addr->pa_start; | 
|  | p->membase = omap_hwmod_get_mpu_rt_va(oh); | 
|  | p->irqflags = IRQF_SHARED; | 
|  | p->private_data = uart; | 
|  |  | 
|  | /* | 
|  | * omap44xx, ti816x: Never read empty UART fifo | 
|  | * omap3xxx: Never read empty UART fifo on UARTs | 
|  | * with IP rev >=0x52 | 
|  | */ | 
|  | uart->regshift = p->regshift; | 
|  | uart->membase = p->membase; | 
|  | if (cpu_is_omap44xx() || cpu_is_ti816x()) | 
|  | uart->errata |= UART_ERRATA_FIFO_FULL_ABORT; | 
|  | else if ((serial_read_reg(uart, UART_OMAP_MVER) & 0xFF) | 
|  | >= UART_OMAP_NO_EMPTY_FIFO_READ_IP_REV) | 
|  | uart->errata |= UART_ERRATA_FIFO_FULL_ABORT; | 
|  |  | 
|  | if (uart->errata & UART_ERRATA_FIFO_FULL_ABORT) { | 
|  | p->serial_in = serial_in_override; | 
|  | p->serial_out = serial_out_override; | 
|  | } | 
|  |  | 
|  | pdata = &ports[0]; | 
|  | pdata_size = 2 * sizeof(struct plat_serial8250_port); | 
|  | #else | 
|  |  | 
|  | name = DRIVER_NAME; | 
|  |  | 
|  | omap_up.dma_enabled = uart->dma_enabled; | 
|  | omap_up.uartclk = OMAP24XX_BASE_BAUD * 16; | 
|  | omap_up.mapbase = oh->slaves[0]->addr->pa_start; | 
|  | omap_up.membase = omap_hwmod_get_mpu_rt_va(oh); | 
|  | omap_up.irqflags = IRQF_SHARED; | 
|  | omap_up.flags = UPF_BOOT_AUTOCONF | UPF_SHARE_IRQ; | 
|  |  | 
|  | pdata = &omap_up; | 
|  | pdata_size = sizeof(struct omap_uart_port_info); | 
|  | #endif | 
|  |  | 
|  | if (WARN_ON(!oh)) | 
|  | return; | 
|  |  | 
|  | pdev = omap_device_build(name, uart->num, oh, pdata, pdata_size, | 
|  | NULL, 0, false); | 
|  | WARN(IS_ERR(pdev), "Could not build omap_device for %s: %s.\n", | 
|  | name, oh->name); | 
|  |  | 
|  | omap_device_disable_idle_on_suspend(pdev); | 
|  | oh->mux = omap_hwmod_mux_init(bdata->pads, bdata->pads_cnt); | 
|  |  | 
|  | uart->irq = oh->mpu_irqs[0].irq; | 
|  | uart->regshift = 2; | 
|  | uart->mapbase = oh->slaves[0]->addr->pa_start; | 
|  | uart->membase = omap_hwmod_get_mpu_rt_va(oh); | 
|  | uart->pdev = pdev; | 
|  |  | 
|  | oh->dev_attr = uart; | 
|  |  | 
|  | console_lock(); /* in case the earlycon is on the UART */ | 
|  |  | 
|  | /* | 
|  | * Because of early UART probing, UART did not get idled | 
|  | * on init.  Now that omap_device is ready, ensure full idle | 
|  | * before doing omap_device_enable(). | 
|  | */ | 
|  | omap_hwmod_idle(uart->oh); | 
|  |  | 
|  | omap_device_enable(uart->pdev); | 
|  | omap_uart_idle_init(uart); | 
|  | omap_uart_reset(uart); | 
|  | omap_hwmod_enable_wakeup(uart->oh); | 
|  | omap_device_idle(uart->pdev); | 
|  |  | 
|  | /* | 
|  | * Need to block sleep long enough for interrupt driven | 
|  | * driver to start.  Console driver is in polling mode | 
|  | * so device needs to be kept enabled while polling driver | 
|  | * is in use. | 
|  | */ | 
|  | if (uart->timeout) | 
|  | uart->timeout = (30 * HZ); | 
|  | omap_uart_block_sleep(uart); | 
|  | uart->timeout = DEFAULT_TIMEOUT; | 
|  |  | 
|  | console_unlock(); | 
|  |  | 
|  | if ((cpu_is_omap34xx() && uart->padconf) || | 
|  | (uart->wk_en && uart->wk_mask)) { | 
|  | device_init_wakeup(&pdev->dev, true); | 
|  | DEV_CREATE_FILE(&pdev->dev, &dev_attr_sleep_timeout); | 
|  | } | 
|  |  | 
|  | /* Enable the MDR1 errata for OMAP3 */ | 
|  | if (cpu_is_omap34xx() && !cpu_is_ti816x()) | 
|  | uart->errata |= UART_ERRATA_i202_MDR1_ACCESS; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * omap_serial_init() - initialize all supported serial ports | 
|  | * | 
|  | * 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_init(void) | 
|  | { | 
|  | 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_init_port(&bdata); | 
|  |  | 
|  | } | 
|  | } |