/*
* MSM 7k/8k High speed uart driver
*
* Copyright (c) 2007-2011, Code Aurora Forum. All rights reserved.
* Copyright (c) 2008 Google Inc.
* Modified: Nick Pelly <npelly@google.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details.
*
* Has optional support for uart power management independent of linux
* suspend/resume:
*
* RX wakeup.
* UART wakeup can be triggered by RX activity (using a wakeup GPIO on the
* UART RX pin). This should only be used if there is not a wakeup
* GPIO on the UART CTS, and the first RX byte is known (for example, with the
* Bluetooth Texas Instruments HCILL protocol), since the first RX byte will
* always be lost. RTS will be asserted even while the UART is off in this mode
* of operation. See msm_serial_hs_platform_data.rx_wakeup_irq.
*/
#include <linux/module.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/dma-mapping.h>
#include <linux/dmapool.h>
#include <linux/wait.h>
#include <linux/workqueue.h>
#include <linux/atomic.h>
#include <asm/irq.h>
#include <mach/hardware.h>
#include <mach/dma.h>
#include <linux/platform_data/msm_serial_hs.h>
/* HSUART Registers */
#define UARTDM_MR1_ADDR 0x0
#define UARTDM_MR2_ADDR 0x4
/* Data Mover result codes */
#define RSLT_FIFO_CNTR_BMSK (0xE << 28)
#define RSLT_VLD BIT(1)
/* write only register */
#define UARTDM_CSR_ADDR 0x8
#define UARTDM_CSR_115200 0xFF
#define UARTDM_CSR_57600 0xEE
#define UARTDM_CSR_38400 0xDD
#define UARTDM_CSR_28800 0xCC
#define UARTDM_CSR_19200 0xBB
#define UARTDM_CSR_14400 0xAA
#define UARTDM_CSR_9600 0x99
#define UARTDM_CSR_7200 0x88
#define UARTDM_CSR_4800 0x77
#define UARTDM_CSR_3600 0x66
#define UARTDM_CSR_2400 0x55
#define UARTDM_CSR_1200 0x44
#define UARTDM_CSR_600 0x33
#define UARTDM_CSR_300 0x22
#define UARTDM_CSR_150 0x11
#define UARTDM_CSR_75 0x00
/* write only register */
#define UARTDM_TF_ADDR 0x70
#define UARTDM_TF2_ADDR 0x74
#define UARTDM_TF3_ADDR 0x78
#define UARTDM_TF4_ADDR 0x7C
/* write only register */
#define UARTDM_CR_ADDR 0x10
#define UARTDM_IMR_ADDR 0x14
#define UARTDM_IPR_ADDR 0x18
#define UARTDM_TFWR_ADDR 0x1c
#define UARTDM_RFWR_ADDR 0x20
#define UARTDM_HCR_ADDR 0x24
#define UARTDM_DMRX_ADDR 0x34
#define UARTDM_IRDA_ADDR 0x38
#define UARTDM_DMEN_ADDR 0x3c
/* UART_DM_NO_CHARS_FOR_TX */
#define UARTDM_NCF_TX_ADDR 0x40
#define UARTDM_BADR_ADDR 0x44
#define UARTDM_SIM_CFG_ADDR 0x80
/* Read Only register */
#define UARTDM_SR_ADDR 0x8
/* Read Only register */
#define UARTDM_RF_ADDR 0x70
#define UARTDM_RF2_ADDR 0x74
#define UARTDM_RF3_ADDR 0x78
#define UARTDM_RF4_ADDR 0x7C
/* Read Only register */
#define UARTDM_MISR_ADDR 0x10
/* Read Only register */
#define UARTDM_ISR_ADDR 0x14
#define UARTDM_RX_TOTAL_SNAP_ADDR 0x38
#define UARTDM_RXFS_ADDR 0x50
/* Register field Mask Mapping */
#define UARTDM_SR_PAR_FRAME_BMSK BIT(5)
#define UARTDM_SR_OVERRUN_BMSK BIT(4)
#define UARTDM_SR_TXEMT_BMSK BIT(3)
#define UARTDM_SR_TXRDY_BMSK BIT(2)
#define UARTDM_SR_RXRDY_BMSK BIT(0)
#define UARTDM_CR_TX_DISABLE_BMSK BIT(3)
#define UARTDM_CR_RX_DISABLE_BMSK BIT(1)
#define UARTDM_CR_TX_EN_BMSK BIT(2)
#define UARTDM_CR_RX_EN_BMSK BIT(0)
/* UARTDM_CR channel_comman bit value (register field is bits 8:4) */
#define RESET_RX 0x10
#define RESET_TX 0x20
#define RESET_ERROR_STATUS 0x30
#define RESET_BREAK_INT 0x40
#define START_BREAK 0x50
#define STOP_BREAK 0x60
#define RESET_CTS 0x70
#define RESET_STALE_INT 0x80
#define RFR_LOW 0xD0
#define RFR_HIGH 0xE0
#define CR_PROTECTION_EN 0x100
#define STALE_EVENT_ENABLE 0x500
#define STALE_EVENT_DISABLE 0x600
#define FORCE_STALE_EVENT 0x400
#define CLEAR_TX_READY 0x300
#define RESET_TX_ERROR 0x800
#define RESET_TX_DONE 0x810
#define UARTDM_MR1_AUTO_RFR_LEVEL1_BMSK 0xffffff00
#define UARTDM_MR1_AUTO_RFR_LEVEL0_BMSK 0x3f
#define UARTDM_MR1_CTS_CTL_BMSK 0x40
#define UARTDM_MR1_RX_RDY_CTL_BMSK 0x80
#define UARTDM_MR2_ERROR_MODE_BMSK 0x40
#define UARTDM_MR2_BITS_PER_CHAR_BMSK 0x30
/* bits per character configuration */
#define FIVE_BPC (0 << 4)
#define SIX_BPC (1 << 4)
#define SEVEN_BPC (2 << 4)
#define EIGHT_BPC (3 << 4)
#define UARTDM_MR2_STOP_BIT_LEN_BMSK 0xc
#define STOP_BIT_ONE (1 << 2)
#define STOP_BIT_TWO (3 << 2)
#define UARTDM_MR2_PARITY_MODE_BMSK 0x3
/* Parity configuration */
#define NO_PARITY 0x0
#define EVEN_PARITY 0x1
#define ODD_PARITY 0x2
#define SPACE_PARITY 0x3
#define UARTDM_IPR_STALE_TIMEOUT_MSB_BMSK 0xffffff80
#define UARTDM_IPR_STALE_LSB_BMSK 0x1f
/* These can be used for both ISR and IMR register */
#define UARTDM_ISR_TX_READY_BMSK BIT(7)
#define UARTDM_ISR_CURRENT_CTS_BMSK BIT(6)
#define UARTDM_ISR_DELTA_CTS_BMSK BIT(5)
#define UARTDM_ISR_RXLEV_BMSK BIT(4)
#define UARTDM_ISR_RXSTALE_BMSK BIT(3)
#define UARTDM_ISR_RXBREAK_BMSK BIT(2)
#define UARTDM_ISR_RXHUNT_BMSK BIT(1)
#define UARTDM_ISR_TXLEV_BMSK BIT(0)
/* Field definitions for UART_DM_DMEN*/
#define UARTDM_TX_DM_EN_BMSK 0x1
#define UARTDM_RX_DM_EN_BMSK 0x2
#define UART_FIFOSIZE 64
#define UARTCLK 7372800
/* Rx DMA request states */
enum flush_reason {
FLUSH_NONE,
FLUSH_DATA_READY,
FLUSH_DATA_INVALID, /* values after this indicate invalid data */
FLUSH_IGNORE = FLUSH_DATA_INVALID,
FLUSH_STOP,
FLUSH_SHUTDOWN,
};
/* UART clock states */
enum msm_hs_clk_states_e {
MSM_HS_CLK_PORT_OFF, /* port not in use */
MSM_HS_CLK_OFF, /* clock disabled */
MSM_HS_CLK_REQUEST_OFF, /* disable after TX and RX flushed */
MSM_HS_CLK_ON, /* clock enabled */
};
/* Track the forced RXSTALE flush during clock off sequence.
* These states are only valid during MSM_HS_CLK_REQUEST_OFF */
enum msm_hs_clk_req_off_state_e {
CLK_REQ_OFF_START,
CLK_REQ_OFF_RXSTALE_ISSUED,
CLK_REQ_OFF_FLUSH_ISSUED,
CLK_REQ_OFF_RXSTALE_FLUSHED,
};
/**
* struct msm_hs_tx
* @tx_ready_int_en: ok to dma more tx?
* @dma_in_flight: tx dma in progress
* @xfer: top level DMA command pointer structure
* @command_ptr: third level command struct pointer
* @command_ptr_ptr: second level command list struct pointer
* @mapped_cmd_ptr: DMA view of third level command struct
* @mapped_cmd_ptr_ptr: DMA view of second level command list struct
* @tx_count: number of bytes to transfer in DMA transfer
* @dma_base: DMA view of UART xmit buffer
*
* This structure describes a single Tx DMA transaction. MSM DMA
* commands have two levels of indirection. The top level command
* ptr points to a list of command ptr which in turn points to a
* single DMA 'command'. In our case each Tx transaction consists
* of a single second level pointer pointing to a 'box type' command.
*/
struct msm_hs_tx {
unsigned int tx_ready_int_en;
unsigned int dma_in_flight;
struct msm_dmov_cmd xfer;
dmov_box *command_ptr;
u32 *command_ptr_ptr;
dma_addr_t mapped_cmd_ptr;
dma_addr_t mapped_cmd_ptr_ptr;
int tx_count;
dma_addr_t dma_base;
};
/**
* struct msm_hs_rx
* @flush: Rx DMA request state
* @xfer: top level DMA command pointer structure
* @cmdptr_dmaaddr: DMA view of second level command structure
* @command_ptr: third level DMA command pointer structure
* @command_ptr_ptr: second level DMA command list pointer
* @mapped_cmd_ptr: DMA view of the third level command structure
* @wait: wait for DMA completion before shutdown
* @buffer: destination buffer for RX DMA
* @rbuffer: DMA view of buffer
* @pool: dma pool out of which coherent rx buffer is allocated
* @tty_work: private work-queue for tty flip buffer push task
*
* This structure describes a single Rx DMA transaction. Rx DMA
* transactions use box mode DMA commands.
*/
struct msm_hs_rx {
enum flush_reason flush;
struct msm_dmov_cmd xfer;
dma_addr_t cmdptr_dmaaddr;
dmov_box *command_ptr;
u32 *command_ptr_ptr;
dma_addr_t mapped_cmd_ptr;
wait_queue_head_t wait;
dma_addr_t rbuffer;
unsigned char *buffer;
struct dma_pool *pool;
struct work_struct tty_work;
};
/**
* struct msm_hs_rx_wakeup
* @irq: IRQ line to be configured as interrupt source on Rx activity
* @ignore: boolean value. 1 = ignore the wakeup interrupt
* @rx_to_inject: extra character to be inserted to Rx tty on wakeup
* @inject_rx: 1 = insert rx_to_inject. 0 = do not insert extra character
*
* This is an optional structure required for UART Rx GPIO IRQ based
* wakeup from low power state. UART wakeup can be triggered by RX activity
* (using a wakeup GPIO on the UART RX pin). This should only be used if
* there is not a wakeup GPIO on the UART CTS, and the first RX byte is
* known (eg., with the Bluetooth Texas Instruments HCILL protocol),
* since the first RX byte will always be lost. RTS will be asserted even
* while the UART is clocked off in this mode of operation.
*/
struct msm_hs_rx_wakeup {
int irq; /* < 0 indicates low power wakeup disabled */
unsigned char ignore;
unsigned char inject_rx;
char rx_to_inject;
};
/**
* struct msm_hs_port
* @uport: embedded uart port structure
* @imr_reg: shadow value of UARTDM_IMR
* @clk: uart input clock handle
* @tx: Tx transaction related data structure
* @rx: Rx transaction related data structure
* @dma_tx_channel: Tx DMA command channel
* @dma_rx_channel Rx DMA command channel
* @dma_tx_crci: Tx channel rate control interface number
* @dma_rx_crci: Rx channel rate control interface number
* @clk_off_timer: Timer to poll DMA event completion before clock off
* @clk_off_delay: clk_off_timer poll interval
* @clk_state: overall clock state
* @clk_req_off_state: post flush clock states
* @rx_wakeup: optional rx_wakeup feature related data
* @exit_lpm_cb: optional callback to exit low power mode
*
* Low level serial port structure.
*/
struct msm_hs_port {
struct uart_port uport;
unsigned long imr_reg;
struct clk *clk;
struct msm_hs_tx tx;
struct msm_hs_rx rx;
int dma_tx_channel;
int dma_rx_channel;
int dma_tx_crci;
int dma_rx_crci;
struct hrtimer clk_off_timer;
ktime_t clk_off_delay;
enum msm_hs_clk_states_e clk_state;
enum msm_hs_clk_req_off_state_e clk_req_off_state;
struct msm_hs_rx_wakeup rx_wakeup;
void (*exit_lpm_cb)(struct uart_port *);
};
#define MSM_UARTDM_BURST_SIZE 16 /* DM burst size (in bytes) */
#define UARTDM_TX_BUF_SIZE UART_XMIT_SIZE
#define UARTDM_RX_BUF_SIZE 512
#define UARTDM_NR 2
static struct msm_hs_port q_uart_port[UARTDM_NR];
static struct platform_driver msm_serial_hs_platform_driver;
static struct uart_driver msm_hs_driver;
static struct uart_ops msm_hs_ops;
static struct workqueue_struct *msm_hs_workqueue;
#define UARTDM_TO_MSM(uart_port) \
container_of((uart_port), struct msm_hs_port, uport)
static unsigned int use_low_power_rx_wakeup(struct msm_hs_port
*msm_uport)
{
return (msm_uport->rx_wakeup.irq >= 0);
}
static unsigned int msm_hs_read(struct uart_port *uport,
unsigned int offset)
{
return ioread32(uport->membase + offset);
}
static void msm_hs_write(struct uart_port *uport, unsigned int offset,
unsigned int value)
{
iowrite32(value, uport->membase + offset);
}
static void msm_hs_release_port(struct uart_port *port)
{
iounmap(port->membase);
}
static int msm_hs_request_port(struct uart_port *port)
{
port->membase = ioremap(port->mapbase, PAGE_SIZE);
if (unlikely(!port->membase))
return -ENOMEM;
/* configure the CR Protection to Enable */
msm_hs_write(port, UARTDM_CR_ADDR, CR_PROTECTION_EN);
return 0;
}
static int msm_hs_remove(struct platform_device *pdev)
{
struct msm_hs_port *msm_uport;
struct device *dev;
if (pdev->id < 0 || pdev->id >= UARTDM_NR) {
printk(KERN_ERR "Invalid plaform device ID = %d\n", pdev->id);
return -EINVAL;
}
msm_uport = &q_uart_port[pdev->id];
dev = msm_uport->uport.dev;
dma_unmap_single(dev, msm_uport->rx.mapped_cmd_ptr, sizeof(dmov_box),
DMA_TO_DEVICE);
dma_pool_free(msm_uport->rx.pool, msm_uport->rx.buffer,
msm_uport->rx.rbuffer);
dma_pool_destroy(msm_uport->rx.pool);
dma_unmap_single(dev, msm_uport->rx.cmdptr_dmaaddr, sizeof(u32),
DMA_TO_DEVICE);
dma_unmap_single(dev, msm_uport->tx.mapped_cmd_ptr_ptr, sizeof(u32),
DMA_TO_DEVICE);
dma_unmap_single(dev, msm_uport->tx.mapped_cmd_ptr, sizeof(dmov_box),
DMA_TO_DEVICE);
uart_remove_one_port(&msm_hs_driver, &msm_uport->uport);
clk_put(msm_uport->clk);
/* Free the tx resources */
kfree(msm_uport->tx.command_ptr);
kfree(msm_uport->tx.command_ptr_ptr);
/* Free the rx resources */
kfree(msm_uport->rx.command_ptr);
kfree(msm_uport->rx.command_ptr_ptr);
iounmap(msm_uport->uport.membase);
return 0;
}
static int msm_hs_init_clk_locked(struct uart_port *uport)
{
int ret;
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
ret = clk_enable(msm_uport->clk);
if (ret) {
printk(KERN_ERR "Error could not turn on UART clk\n");
return ret;
}
/* Set up the MREG/NREG/DREG/MNDREG */
ret = clk_set_rate(msm_uport->clk, uport->uartclk);
if (ret) {
printk(KERN_WARNING "Error setting clock rate on UART\n");
clk_disable(msm_uport->clk);
return ret;
}
msm_uport->clk_state = MSM_HS_CLK_ON;
return 0;
}
/* Enable and Disable clocks (Used for power management) */
static void msm_hs_pm(struct uart_port *uport, unsigned int state,
unsigned int oldstate)
{
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
if (use_low_power_rx_wakeup(msm_uport) ||
msm_uport->exit_lpm_cb)
return; /* ignore linux PM states,
use msm_hs_request_clock API */
switch (state) {
case 0:
clk_enable(msm_uport->clk);
break;
case 3:
clk_disable(msm_uport->clk);
break;
default:
dev_err(uport->dev, "msm_serial: Unknown PM state %d\n",
state);
}
}
/*
* programs the UARTDM_CSR register with correct bit rates
*
* Interrupts should be disabled before we are called, as
* we modify Set Baud rate
* Set receive stale interrupt level, dependent on Bit Rate
* Goal is to have around 8 ms before indicate stale.
* roundup (((Bit Rate * .008) / 10) + 1
*/
static void msm_hs_set_bps_locked(struct uart_port *uport,
unsigned int bps)
{
unsigned long rxstale;
unsigned long data;
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
switch (bps) {
case 300:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_75);
rxstale = 1;
break;
case 600:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_150);
rxstale = 1;
break;
case 1200:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_300);
rxstale = 1;
break;
case 2400:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_600);
rxstale = 1;
break;
case 4800:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_1200);
rxstale = 1;
break;
case 9600:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_2400);
rxstale = 2;
break;
case 14400:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_3600);
rxstale = 3;
break;
case 19200:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_4800);
rxstale = 4;
break;
case 28800:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_7200);
rxstale = 6;
break;
case 38400:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_9600);
rxstale = 8;
break;
case 57600:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_14400);
rxstale = 16;
break;
case 76800:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_19200);
rxstale = 16;
break;
case 115200:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_28800);
rxstale = 31;
break;
case 230400:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_57600);
rxstale = 31;
break;
case 460800:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_115200);
rxstale = 31;
break;
case 4000000:
case 3686400:
case 3200000:
case 3500000:
case 3000000:
case 2500000:
case 1500000:
case 1152000:
case 1000000:
case 921600:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_115200);
rxstale = 31;
break;
default:
msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_2400);
/* default to 9600 */
bps = 9600;
rxstale = 2;
break;
}
if (bps > 460800)
uport->uartclk = bps * 16;
else
uport->uartclk = UARTCLK;
if (clk_set_rate(msm_uport->clk, uport->uartclk)) {
printk(KERN_WARNING "Error setting clock rate on UART\n");
return;
}
data = rxstale & UARTDM_IPR_STALE_LSB_BMSK;
data |= UARTDM_IPR_STALE_TIMEOUT_MSB_BMSK & (rxstale << 2);
msm_hs_write(uport, UARTDM_IPR_ADDR, data);
}
/*
* termios : new ktermios
* oldtermios: old ktermios previous setting
*
* Configure the serial port
*/
static void msm_hs_set_termios(struct uart_port *uport,
struct ktermios *termios,
struct ktermios *oldtermios)
{
unsigned int bps;
unsigned long data;
unsigned long flags;
unsigned int c_cflag = termios->c_cflag;
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
spin_lock_irqsave(&uport->lock, flags);
clk_enable(msm_uport->clk);
/* 300 is the minimum baud support by the driver */
bps = uart_get_baud_rate(uport, termios, oldtermios, 200, 4000000);
/* Temporary remapping 200 BAUD to 3.2 mbps */
if (bps == 200)
bps = 3200000;
msm_hs_set_bps_locked(uport, bps);
data = msm_hs_read(uport, UARTDM_MR2_ADDR);
data &= ~UARTDM_MR2_PARITY_MODE_BMSK;
/* set parity */
if (PARENB == (c_cflag & PARENB)) {
if (PARODD == (c_cflag & PARODD))
data |= ODD_PARITY;
else if (CMSPAR == (c_cflag & CMSPAR))
data |= SPACE_PARITY;
else
data |= EVEN_PARITY;
}
/* Set bits per char */
data &= ~UARTDM_MR2_BITS_PER_CHAR_BMSK;
switch (c_cflag & CSIZE) {
case CS5:
data |= FIVE_BPC;
break;
case CS6:
data |= SIX_BPC;
break;
case CS7:
data |= SEVEN_BPC;
break;
default:
data |= EIGHT_BPC;
break;
}
/* stop bits */
if (c_cflag & CSTOPB) {
data |= STOP_BIT_TWO;
} else {
/* otherwise 1 stop bit */
data |= STOP_BIT_ONE;
}
data |= UARTDM_MR2_ERROR_MODE_BMSK;
/* write parity/bits per char/stop bit configuration */
msm_hs_write(uport, UARTDM_MR2_ADDR, data);
/* Configure HW flow control */
data = msm_hs_read(uport, UARTDM_MR1_ADDR);
data &= ~(UARTDM_MR1_CTS_CTL_BMSK | UARTDM_MR1_RX_RDY_CTL_BMSK);
if (c_cflag & CRTSCTS) {
data |= UARTDM_MR1_CTS_CTL_BMSK;
data |= UARTDM_MR1_RX_RDY_CTL_BMSK;
}
msm_hs_write(uport, UARTDM_MR1_ADDR, data);
uport->ignore_status_mask = termios->c_iflag & INPCK;
uport->ignore_status_mask |= termios->c_iflag & IGNPAR;
uport->read_status_mask = (termios->c_cflag & CREAD);
msm_hs_write(uport, UARTDM_IMR_ADDR, 0);
/* Set Transmit software time out */
uart_update_timeout(uport, c_cflag, bps);
msm_hs_write(uport, UARTDM_CR_ADDR, RESET_RX);
msm_hs_write(uport, UARTDM_CR_ADDR, RESET_TX);
if (msm_uport->rx.flush == FLUSH_NONE) {
msm_uport->rx.flush = FLUSH_IGNORE;
msm_dmov_stop_cmd(msm_uport->dma_rx_channel, NULL, 1);
}
msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
clk_disable(msm_uport->clk);
spin_unlock_irqrestore(&uport->lock, flags);
}
/*
* Standard API, Transmitter
* Any character in the transmit shift register is sent
*/
static unsigned int msm_hs_tx_empty(struct uart_port *uport)
{
unsigned int data;
unsigned int ret = 0;
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
clk_enable(msm_uport->clk);
data = msm_hs_read(uport, UARTDM_SR_ADDR);
if (data & UARTDM_SR_TXEMT_BMSK)
ret = TIOCSER_TEMT;
clk_disable(msm_uport->clk);
return ret;
}
/*
* Standard API, Stop transmitter.
* Any character in the transmit shift register is sent as
* well as the current data mover transfer .
*/
static void msm_hs_stop_tx_locked(struct uart_port *uport)
{
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
msm_uport->tx.tx_ready_int_en = 0;
}
/*
* Standard API, Stop receiver as soon as possible.
*
* Function immediately terminates the operation of the
* channel receiver and any incoming characters are lost. None
* of the receiver status bits are affected by this command and
* characters that are already in the receive FIFO there.
*/
static void msm_hs_stop_rx_locked(struct uart_port *uport)
{
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
unsigned int data;
clk_enable(msm_uport->clk);
/* disable dlink */
data = msm_hs_read(uport, UARTDM_DMEN_ADDR);
data &= ~UARTDM_RX_DM_EN_BMSK;
msm_hs_write(uport, UARTDM_DMEN_ADDR, data);
/* Disable the receiver */
if (msm_uport->rx.flush == FLUSH_NONE)
msm_dmov_stop_cmd(msm_uport->dma_rx_channel, NULL, 1);
if (msm_uport->rx.flush != FLUSH_SHUTDOWN)
msm_uport->rx.flush = FLUSH_STOP;
clk_disable(msm_uport->clk);
}
/* Transmit the next chunk of data */
static void msm_hs_submit_tx_locked(struct uart_port *uport)
{
int left;
int tx_count;
dma_addr_t src_addr;
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
struct msm_hs_tx *tx = &msm_uport->tx;
struct circ_buf *tx_buf = &msm_uport->uport.state->xmit;
if (uart_circ_empty(tx_buf) || uport->state->port.tty->stopped) {
msm_hs_stop_tx_locked(uport);
return;
}
tx->dma_in_flight = 1;
tx_count = uart_circ_chars_pending(tx_buf);
if (UARTDM_TX_BUF_SIZE < tx_count)
tx_count = UARTDM_TX_BUF_SIZE;
left = UART_XMIT_SIZE - tx_buf->tail;
if (tx_count > left)
tx_count = left;
src_addr = tx->dma_base + tx_buf->tail;
dma_sync_single_for_device(uport->dev, src_addr, tx_count,
DMA_TO_DEVICE);
tx->command_ptr->num_rows = (((tx_count + 15) >> 4) << 16) |
((tx_count + 15) >> 4);
tx->command_ptr->src_row_addr = src_addr;
dma_sync_single_for_device(uport->dev, tx->mapped_cmd_ptr,
sizeof(dmov_box), DMA_TO_DEVICE);
*tx->command_ptr_ptr = CMD_PTR_LP | DMOV_CMD_ADDR(tx->mapped_cmd_ptr);
dma_sync_single_for_device(uport->dev, tx->mapped_cmd_ptr_ptr,
sizeof(u32), DMA_TO_DEVICE);
/* Save tx_count to use in Callback */
tx->tx_count = tx_count;
msm_hs_write(uport, UARTDM_NCF_TX_ADDR, tx_count);
/* Disable the tx_ready interrupt */
msm_uport->imr_reg &= ~UARTDM_ISR_TX_READY_BMSK;
msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
msm_dmov_enqueue_cmd(msm_uport->dma_tx_channel, &tx->xfer);
}
/* Start to receive the next chunk of data */
static void msm_hs_start_rx_locked(struct uart_port *uport)
{
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
msm_hs_write(uport, UARTDM_CR_ADDR, RESET_STALE_INT);
msm_hs_write(uport, UARTDM_DMRX_ADDR, UARTDM_RX_BUF_SIZE);
msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_ENABLE);
msm_uport->imr_reg |= UARTDM_ISR_RXLEV_BMSK;
msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
msm_uport->rx.flush = FLUSH_NONE;
msm_dmov_enqueue_cmd(msm_uport->dma_rx_channel, &msm_uport->rx.xfer);
/* might have finished RX and be ready to clock off */
hrtimer_start(&msm_uport->clk_off_timer, msm_uport->clk_off_delay,
HRTIMER_MODE_REL);
}
/* Enable the transmitter Interrupt */
static void msm_hs_start_tx_locked(struct uart_port *uport)
{
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
clk_enable(msm_uport->clk);
if (msm_uport->exit_lpm_cb)
msm_uport->exit_lpm_cb(uport);
if (msm_uport->tx.tx_ready_int_en == 0) {
msm_uport->tx.tx_ready_int_en = 1;
msm_hs_submit_tx_locked(uport);
}
clk_disable(msm_uport->clk);
}
/*
* This routine is called when we are done with a DMA transfer
*
* This routine is registered with Data mover when we set
* up a Data Mover transfer. It is called from Data mover ISR
* when the DMA transfer is done.
*/
static void msm_hs_dmov_tx_callback(struct msm_dmov_cmd *cmd_ptr,
unsigned int result,
struct msm_dmov_errdata *err)
{
unsigned long flags;
struct msm_hs_port *msm_uport;
/* DMA did not finish properly */
WARN_ON((((result & RSLT_FIFO_CNTR_BMSK) >> 28) == 1) &&
!(result & RSLT_VLD));
msm_uport = container_of(cmd_ptr, struct msm_hs_port, tx.xfer);
spin_lock_irqsave(&msm_uport->uport.lock, flags);
clk_enable(msm_uport->clk);
msm_uport->imr_reg |= UARTDM_ISR_TX_READY_BMSK;
msm_hs_write(&msm_uport->uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
clk_disable(msm_uport->clk);
spin_unlock_irqrestore(&msm_uport->uport.lock, flags);
}
/*
* This routine is called when we are done with a DMA transfer or the
* a flush has been sent to the data mover driver.
*
* This routine is registered with Data mover when we set up a Data Mover
* transfer. It is called from Data mover ISR when the DMA transfer is done.
*/
static void msm_hs_dmov_rx_callback(struct msm_dmov_cmd *cmd_ptr,
unsigned int result,
struct msm_dmov_errdata *err)
{
int retval;
int rx_count;
unsigned long status;
unsigned int error_f = 0;
unsigned long flags;
unsigned int flush;
struct tty_port *port;
struct uart_port *uport;
struct msm_hs_port *msm_uport;
msm_uport = container_of(cmd_ptr, struct msm_hs_port, rx.xfer);
uport = &msm_uport->uport;
spin_lock_irqsave(&uport->lock, flags);
clk_enable(msm_uport->clk);
port = &uport->state->port;
msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_DISABLE);
status = msm_hs_read(uport, UARTDM_SR_ADDR);
/* overflow is not connect to data in a FIFO */
if (unlikely((status & UARTDM_SR_OVERRUN_BMSK) &&
(uport->read_status_mask & CREAD))) {
tty_insert_flip_char(port, 0, TTY_OVERRUN);
uport->icount.buf_overrun++;
error_f = 1;
}
if (!(uport->ignore_status_mask & INPCK))
status = status & ~(UARTDM_SR_PAR_FRAME_BMSK);
if (unlikely(status & UARTDM_SR_PAR_FRAME_BMSK)) {
/* Can not tell difference between parity & frame error */
uport->icount.parity++;
error_f = 1;
if (uport->ignore_status_mask & IGNPAR)
tty_insert_flip_char(port, 0, TTY_PARITY);
}
if (error_f)
msm_hs_write(uport, UARTDM_CR_ADDR, RESET_ERROR_STATUS);
if (msm_uport->clk_req_off_state == CLK_REQ_OFF_FLUSH_ISSUED)
msm_uport->clk_req_off_state = CLK_REQ_OFF_RXSTALE_FLUSHED;
flush = msm_uport->rx.flush;
if (flush == FLUSH_IGNORE)
msm_hs_start_rx_locked(uport);
if (flush == FLUSH_STOP)
msm_uport->rx.flush = FLUSH_SHUTDOWN;
if (flush >= FLUSH_DATA_INVALID)
goto out;
rx_count = msm_hs_read(uport, UARTDM_RX_TOTAL_SNAP_ADDR);
if (0 != (uport->read_status_mask & CREAD)) {
retval = tty_insert_flip_string(port, msm_uport->rx.buffer,
rx_count);
BUG_ON(retval != rx_count);
}
msm_hs_start_rx_locked(uport);
out:
clk_disable(msm_uport->clk);
spin_unlock_irqrestore(&uport->lock, flags);
if (flush < FLUSH_DATA_INVALID)
queue_work(msm_hs_workqueue, &msm_uport->rx.tty_work);
}
static void msm_hs_tty_flip_buffer_work(struct work_struct *work)
{
struct msm_hs_port *msm_uport =
container_of(work, struct msm_hs_port, rx.tty_work);
tty_flip_buffer_push(&msm_uport->uport.state->port);
}
/*
* Standard API, Current states of modem control inputs
*
* Since CTS can be handled entirely by HARDWARE we always
* indicate clear to send and count on the TX FIFO to block when
* it fills up.
*
* - TIOCM_DCD
* - TIOCM_CTS
* - TIOCM_DSR
* - TIOCM_RI
* (Unsupported) DCD and DSR will return them high. RI will return low.
*/
static unsigned int msm_hs_get_mctrl_locked(struct uart_port *uport)
{
return TIOCM_DSR | TIOCM_CAR | TIOCM_CTS;
}
/*
* True enables UART auto RFR, which indicates we are ready for data if the RX
* buffer is not full. False disables auto RFR, and deasserts RFR to indicate
* we are not ready for data. Must be called with UART clock on.
*/
static void set_rfr_locked(struct uart_port *uport, int auto_rfr)
{
unsigned int data;
data = msm_hs_read(uport, UARTDM_MR1_ADDR);
if (auto_rfr) {
/* enable auto ready-for-receiving */
data |= UARTDM_MR1_RX_RDY_CTL_BMSK;
msm_hs_write(uport, UARTDM_MR1_ADDR, data);
} else {
/* disable auto ready-for-receiving */
data &= ~UARTDM_MR1_RX_RDY_CTL_BMSK;
msm_hs_write(uport, UARTDM_MR1_ADDR, data);
/* RFR is active low, set high */
msm_hs_write(uport, UARTDM_CR_ADDR, RFR_HIGH);
}
}
/*
* Standard API, used to set or clear RFR
*/
static void msm_hs_set_mctrl_locked(struct uart_port *uport,
unsigned int mctrl)
{
unsigned int auto_rfr;
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
clk_enable(msm_uport->clk);
auto_rfr = TIOCM_RTS & mctrl ? 1 : 0;
set_rfr_locked(uport, auto_rfr);
clk_disable(msm_uport->clk);
}
/* Standard API, Enable modem status (CTS) interrupt */
static void msm_hs_enable_ms_locked(struct uart_port *uport)
{
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
clk_enable(msm_uport->clk);
/* Enable DELTA_CTS Interrupt */
msm_uport->imr_reg |= UARTDM_ISR_DELTA_CTS_BMSK;
msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
clk_disable(msm_uport->clk);
}
/*
* Standard API, Break Signal
*
* Control the transmission of a break signal. ctl eq 0 => break
* signal terminate ctl ne 0 => start break signal
*/
static void msm_hs_break_ctl(struct uart_port *uport, int ctl)
{
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
clk_enable(msm_uport->clk);
msm_hs_write(uport, UARTDM_CR_ADDR, ctl ? START_BREAK : STOP_BREAK);
clk_disable(msm_uport->clk);
}
static void msm_hs_config_port(struct uart_port *uport, int cfg_flags)
{
unsigned long flags;
spin_lock_irqsave(&uport->lock, flags);
if (cfg_flags & UART_CONFIG_TYPE) {
uport->type = PORT_MSM;
msm_hs_request_port(uport);
}
spin_unlock_irqrestore(&uport->lock, flags);
}
/* Handle CTS changes (Called from interrupt handler) */
static void msm_hs_handle_delta_cts_locked(struct uart_port *uport)
{
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
clk_enable(msm_uport->clk);
/* clear interrupt */
msm_hs_write(uport, UARTDM_CR_ADDR, RESET_CTS);
uport->icount.cts++;
clk_disable(msm_uport->clk);
/* clear the IOCTL TIOCMIWAIT if called */
wake_up_interruptible(&uport->state->port.delta_msr_wait);
}
/* check if the TX path is flushed, and if so clock off
* returns 0 did not clock off, need to retry (still sending final byte)
* -1 did not clock off, do not retry
* 1 if we clocked off
*/
static int msm_hs_check_clock_off_locked(struct uart_port *uport)
{
unsigned long sr_status;
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
struct circ_buf *tx_buf = &uport->state->xmit;
/* Cancel if tx tty buffer is not empty, dma is in flight,
* or tx fifo is not empty, or rx fifo is not empty */
if (msm_uport->clk_state != MSM_HS_CLK_REQUEST_OFF ||
!uart_circ_empty(tx_buf) || msm_uport->tx.dma_in_flight ||
(msm_uport->imr_reg & UARTDM_ISR_TXLEV_BMSK) ||
!(msm_uport->imr_reg & UARTDM_ISR_RXLEV_BMSK)) {
return -1;
}
/* Make sure the uart is finished with the last byte */
sr_status = msm_hs_read(uport, UARTDM_SR_ADDR);
if (!(sr_status & UARTDM_SR_TXEMT_BMSK))
return 0; /* retry */
/* Make sure forced RXSTALE flush complete */
switch (msm_uport->clk_req_off_state) {
case CLK_REQ_OFF_START:
msm_uport->clk_req_off_state = CLK_REQ_OFF_RXSTALE_ISSUED;
msm_hs_write(uport, UARTDM_CR_ADDR, FORCE_STALE_EVENT);
return 0; /* RXSTALE flush not complete - retry */
case CLK_REQ_OFF_RXSTALE_ISSUED:
case CLK_REQ_OFF_FLUSH_ISSUED:
return 0; /* RXSTALE flush not complete - retry */
case CLK_REQ_OFF_RXSTALE_FLUSHED:
break; /* continue */
}
if (msm_uport->rx.flush != FLUSH_SHUTDOWN) {
if (msm_uport->rx.flush == FLUSH_NONE)
msm_hs_stop_rx_locked(uport);
return 0; /* come back later to really clock off */
}
/* we really want to clock off */
clk_disable(msm_uport->clk);
msm_uport->clk_state = MSM_HS_CLK_OFF;
if (use_low_power_rx_wakeup(msm_uport)) {
msm_uport->rx_wakeup.ignore = 1;
enable_irq(msm_uport->rx_wakeup.irq);
}
return 1;
}
static enum hrtimer_restart msm_hs_clk_off_retry(struct hrtimer *timer)
{
unsigned long flags;
int ret = HRTIMER_NORESTART;
struct msm_hs_port *msm_uport = container_of(timer, struct msm_hs_port,
clk_off_timer);
struct uart_port *uport = &msm_uport->uport;
spin_lock_irqsave(&uport->lock, flags);
if (!msm_hs_check_clock_off_locked(uport)) {
hrtimer_forward_now(timer, msm_uport->clk_off_delay);
ret = HRTIMER_RESTART;
}
spin_unlock_irqrestore(&uport->lock, flags);
return ret;
}
static irqreturn_t msm_hs_isr(int irq, void *dev)
{
unsigned long flags;
unsigned long isr_status;
struct msm_hs_port *msm_uport = dev;
struct uart_port *uport = &msm_uport->uport;
struct circ_buf *tx_buf = &uport->state->xmit;
struct msm_hs_tx *tx = &msm_uport->tx;
struct msm_hs_rx *rx = &msm_uport->rx;
spin_lock_irqsave(&uport->lock, flags);
isr_status = msm_hs_read(uport, UARTDM_MISR_ADDR);
/* Uart RX starting */
if (isr_status & UARTDM_ISR_RXLEV_BMSK) {
msm_uport->imr_reg &= ~UARTDM_ISR_RXLEV_BMSK;
msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
}
/* Stale rx interrupt */
if (isr_status & UARTDM_ISR_RXSTALE_BMSK) {
msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_DISABLE);
msm_hs_write(uport, UARTDM_CR_ADDR, RESET_STALE_INT);
if (msm_uport->clk_req_off_state == CLK_REQ_OFF_RXSTALE_ISSUED)
msm_uport->clk_req_off_state =
CLK_REQ_OFF_FLUSH_ISSUED;
if (rx->flush == FLUSH_NONE) {
rx->flush = FLUSH_DATA_READY;
msm_dmov_stop_cmd(msm_uport->dma_rx_channel, NULL, 1);
}
}
/* tx ready interrupt */
if (isr_status & UARTDM_ISR_TX_READY_BMSK) {
/* Clear TX Ready */
msm_hs_write(uport, UARTDM_CR_ADDR, CLEAR_TX_READY);
if (msm_uport->clk_state == MSM_HS_CLK_REQUEST_OFF) {
msm_uport->imr_reg |= UARTDM_ISR_TXLEV_BMSK;
msm_hs_write(uport, UARTDM_IMR_ADDR,
msm_uport->imr_reg);
}
/* Complete DMA TX transactions and submit new transactions */
tx_buf->tail = (tx_buf->tail + tx->tx_count) & ~UART_XMIT_SIZE;
tx->dma_in_flight = 0;
uport->icount.tx += tx->tx_count;
if (tx->tx_ready_int_en)
msm_hs_submit_tx_locked(uport);
if (uart_circ_chars_pending(tx_buf) < WAKEUP_CHARS)
uart_write_wakeup(uport);
}
if (isr_status & UARTDM_ISR_TXLEV_BMSK) {
/* TX FIFO is empty */
msm_uport->imr_reg &= ~UARTDM_ISR_TXLEV_BMSK;
msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
if (!msm_hs_check_clock_off_locked(uport))
hrtimer_start(&msm_uport->clk_off_timer,
msm_uport->clk_off_delay,
HRTIMER_MODE_REL);
}
/* Change in CTS interrupt */
if (isr_status & UARTDM_ISR_DELTA_CTS_BMSK)
msm_hs_handle_delta_cts_locked(uport);
spin_unlock_irqrestore(&uport->lock, flags);
return IRQ_HANDLED;
}
void msm_hs_request_clock_off_locked(struct uart_port *uport)
{
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
if (msm_uport->clk_state == MSM_HS_CLK_ON) {
msm_uport->clk_state = MSM_HS_CLK_REQUEST_OFF;
msm_uport->clk_req_off_state = CLK_REQ_OFF_START;
if (!use_low_power_rx_wakeup(msm_uport))
set_rfr_locked(uport, 0);
msm_uport->imr_reg |= UARTDM_ISR_TXLEV_BMSK;
msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
}
}
/**
* msm_hs_request_clock_off - request to (i.e. asynchronously) turn off uart
* clock once pending TX is flushed and Rx DMA command is terminated.
* @uport: uart_port structure for the device instance.
*
* This functions puts the device into a partially active low power mode. It
* waits to complete all pending tx transactions, flushes ongoing Rx DMA
* command and terminates UART side Rx transaction, puts UART HW in non DMA
* mode and then clocks off the device. A client calls this when no UART
* data is expected. msm_request_clock_on() must be called before any further
* UART can be sent or received.
*/
void msm_hs_request_clock_off(struct uart_port *uport)
{
unsigned long flags;
spin_lock_irqsave(&uport->lock, flags);
msm_hs_request_clock_off_locked(uport);
spin_unlock_irqrestore(&uport->lock, flags);
}
void msm_hs_request_clock_on_locked(struct uart_port *uport)
{
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
unsigned int data;
switch (msm_uport->clk_state) {
case MSM_HS_CLK_OFF:
clk_enable(msm_uport->clk);
disable_irq_nosync(msm_uport->rx_wakeup.irq);
/* fall-through */
case MSM_HS_CLK_REQUEST_OFF:
if (msm_uport->rx.flush == FLUSH_STOP ||
msm_uport->rx.flush == FLUSH_SHUTDOWN) {
msm_hs_write(uport, UARTDM_CR_ADDR, RESET_RX);
data = msm_hs_read(uport, UARTDM_DMEN_ADDR);
data |= UARTDM_RX_DM_EN_BMSK;
msm_hs_write(uport, UARTDM_DMEN_ADDR, data);
}
hrtimer_try_to_cancel(&msm_uport->clk_off_timer);
if (msm_uport->rx.flush == FLUSH_SHUTDOWN)
msm_hs_start_rx_locked(uport);
if (!use_low_power_rx_wakeup(msm_uport))
set_rfr_locked(uport, 1);
if (msm_uport->rx.flush == FLUSH_STOP)
msm_uport->rx.flush = FLUSH_IGNORE;
msm_uport->clk_state = MSM_HS_CLK_ON;
break;
case MSM_HS_CLK_ON:
break;
case MSM_HS_CLK_PORT_OFF:
break;
}
}
/**
* msm_hs_request_clock_on - Switch the device from partially active low
* power mode to fully active (i.e. clock on) mode.
* @uport: uart_port structure for the device.
*
* This function switches on the input clock, puts UART HW into DMA mode
* and enqueues an Rx DMA command if the device was in partially active
* mode. It has no effect if called with the device in inactive state.
*/
void msm_hs_request_clock_on(struct uart_port *uport)
{
unsigned long flags;
spin_lock_irqsave(&uport->lock, flags);
msm_hs_request_clock_on_locked(uport);
spin_unlock_irqrestore(&uport->lock, flags);
}
static irqreturn_t msm_hs_rx_wakeup_isr(int irq, void *dev)
{
unsigned int wakeup = 0;
unsigned long flags;
struct msm_hs_port *msm_uport = dev;
struct uart_port *uport = &msm_uport->uport;
spin_lock_irqsave(&uport->lock, flags);
if (msm_uport->clk_state == MSM_HS_CLK_OFF) {
/* ignore the first irq - it is a pending irq that occurred
* before enable_irq() */
if (msm_uport->rx_wakeup.ignore)
msm_uport->rx_wakeup.ignore = 0;
else
wakeup = 1;
}
if (wakeup) {
/* the uart was clocked off during an rx, wake up and
* optionally inject char into tty rx */
msm_hs_request_clock_on_locked(uport);
if (msm_uport->rx_wakeup.inject_rx) {
tty_insert_flip_char(&uport->state->port,
msm_uport->rx_wakeup.rx_to_inject,
TTY_NORMAL);
queue_work(msm_hs_workqueue, &msm_uport->rx.tty_work);
}
}
spin_unlock_irqrestore(&uport->lock, flags);
return IRQ_HANDLED;
}
static const char *msm_hs_type(struct uart_port *port)
{
return (port->type == PORT_MSM) ? "MSM_HS_UART" : NULL;
}
/* Called when port is opened */
static int msm_hs_startup(struct uart_port *uport)
{
int ret;
int rfr_level;
unsigned long flags;
unsigned int data;
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
struct circ_buf *tx_buf = &uport->state->xmit;
struct msm_hs_tx *tx = &msm_uport->tx;
struct msm_hs_rx *rx = &msm_uport->rx;
rfr_level = uport->fifosize;
if (rfr_level > 16)
rfr_level -= 16;
tx->dma_base = dma_map_single(uport->dev, tx_buf->buf, UART_XMIT_SIZE,
DMA_TO_DEVICE);
/* do not let tty layer execute RX in global workqueue, use a
* dedicated workqueue managed by this driver */
uport->state->port.low_latency = 1;
/* turn on uart clk */
ret = msm_hs_init_clk_locked(uport);
if (unlikely(ret)) {
printk(KERN_ERR "Turning uartclk failed!\n");
goto err_msm_hs_init_clk;
}
/* Set auto RFR Level */
data = msm_hs_read(uport, UARTDM_MR1_ADDR);
data &= ~UARTDM_MR1_AUTO_RFR_LEVEL1_BMSK;
data &= ~UARTDM_MR1_AUTO_RFR_LEVEL0_BMSK;
data |= (UARTDM_MR1_AUTO_RFR_LEVEL1_BMSK & (rfr_level << 2));
data |= (UARTDM_MR1_AUTO_RFR_LEVEL0_BMSK & rfr_level);
msm_hs_write(uport, UARTDM_MR1_ADDR, data);
/* Make sure RXSTALE count is non-zero */
data = msm_hs_read(uport, UARTDM_IPR_ADDR);
if (!data) {
data |= 0x1f & UARTDM_IPR_STALE_LSB_BMSK;
msm_hs_write(uport, UARTDM_IPR_ADDR, data);
}
/* Enable Data Mover Mode */
data = UARTDM_TX_DM_EN_BMSK | UARTDM_RX_DM_EN_BMSK;
msm_hs_write(uport, UARTDM_DMEN_ADDR, data);
/* Reset TX */
msm_hs_write(uport, UARTDM_CR_ADDR, RESET_TX);
msm_hs_write(uport, UARTDM_CR_ADDR, RESET_RX);
msm_hs_write(uport, UARTDM_CR_ADDR, RESET_ERROR_STATUS);
msm_hs_write(uport, UARTDM_CR_ADDR, RESET_BREAK_INT);
msm_hs_write(uport, UARTDM_CR_ADDR, RESET_STALE_INT);
msm_hs_write(uport, UARTDM_CR_ADDR, RESET_CTS);
msm_hs_write(uport, UARTDM_CR_ADDR, RFR_LOW);
/* Turn on Uart Receiver */
msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_RX_EN_BMSK);
/* Turn on Uart Transmitter */
msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_TX_EN_BMSK);
/* Initialize the tx */
tx->tx_ready_int_en = 0;
tx->dma_in_flight = 0;
tx->xfer.complete_func = msm_hs_dmov_tx_callback;
tx->xfer.execute_func = NULL;
tx->command_ptr->cmd = CMD_LC |
CMD_DST_CRCI(msm_uport->dma_tx_crci) | CMD_MODE_BOX;
tx->command_ptr->src_dst_len = (MSM_UARTDM_BURST_SIZE << 16)
| (MSM_UARTDM_BURST_SIZE);
tx->command_ptr->row_offset = (MSM_UARTDM_BURST_SIZE << 16);
tx->command_ptr->dst_row_addr =
msm_uport->uport.mapbase + UARTDM_TF_ADDR;
/* Turn on Uart Receive */
rx->xfer.complete_func = msm_hs_dmov_rx_callback;
rx->xfer.execute_func = NULL;
rx->command_ptr->cmd = CMD_LC |
CMD_SRC_CRCI(msm_uport->dma_rx_crci) | CMD_MODE_BOX;
rx->command_ptr->src_dst_len = (MSM_UARTDM_BURST_SIZE << 16)
| (MSM_UARTDM_BURST_SIZE);
rx->command_ptr->row_offset = MSM_UARTDM_BURST_SIZE;
rx->command_ptr->src_row_addr = uport->mapbase + UARTDM_RF_ADDR;
msm_uport->imr_reg |= UARTDM_ISR_RXSTALE_BMSK;
/* Enable reading the current CTS, no harm even if CTS is ignored */
msm_uport->imr_reg |= UARTDM_ISR_CURRENT_CTS_BMSK;
msm_hs_write(uport, UARTDM_TFWR_ADDR, 0); /* TXLEV on empty TX fifo */
ret = request_irq(uport->irq, msm_hs_isr, IRQF_TRIGGER_HIGH,
"msm_hs_uart", msm_uport);
if (unlikely(ret)) {
printk(KERN_ERR "Request msm_hs_uart IRQ failed!\n");
goto err_request_irq;
}
if (use_low_power_rx_wakeup(msm_uport)) {
ret = request_irq(msm_uport->rx_wakeup.irq,
msm_hs_rx_wakeup_isr,
IRQF_TRIGGER_FALLING,
"msm_hs_rx_wakeup", msm_uport);
if (unlikely(ret)) {
printk(KERN_ERR "Request msm_hs_rx_wakeup IRQ failed!\n");
free_irq(uport->irq, msm_uport);
goto err_request_irq;
}
disable_irq(msm_uport->rx_wakeup.irq);
}
spin_lock_irqsave(&uport->lock, flags);
msm_hs_write(uport, UARTDM_RFWR_ADDR, 0);
msm_hs_start_rx_locked(uport);
spin_unlock_irqrestore(&uport->lock, flags);
ret = pm_runtime_set_active(uport->dev);
if (ret)
dev_err(uport->dev, "set active error:%d\n", ret);
pm_runtime_enable(uport->dev);
return 0;
err_request_irq:
err_msm_hs_init_clk:
dma_unmap_single(uport->dev, tx->dma_base,
UART_XMIT_SIZE, DMA_TO_DEVICE);
return ret;
}
/* Initialize tx and rx data structures */
static int uartdm_init_port(struct uart_port *uport)
{
int ret = 0;
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
struct msm_hs_tx *tx = &msm_uport->tx;
struct msm_hs_rx *rx = &msm_uport->rx;
/* Allocate the command pointer. Needs to be 64 bit aligned */
tx->command_ptr = kmalloc(sizeof(dmov_box), GFP_KERNEL | __GFP_DMA);
if (!tx->command_ptr)
return -ENOMEM;
tx->command_ptr_ptr = kmalloc(sizeof(u32), GFP_KERNEL | __GFP_DMA);
if (!tx->command_ptr_ptr) {
ret = -ENOMEM;
goto err_tx_command_ptr_ptr;
}
tx->mapped_cmd_ptr = dma_map_single(uport->dev, tx->command_ptr,
sizeof(dmov_box), DMA_TO_DEVICE);
tx->mapped_cmd_ptr_ptr = dma_map_single(uport->dev,
tx->command_ptr_ptr,
sizeof(u32), DMA_TO_DEVICE);
tx->xfer.cmdptr = DMOV_CMD_ADDR(tx->mapped_cmd_ptr_ptr);
init_waitqueue_head(&rx->wait);
rx->pool = dma_pool_create("rx_buffer_pool", uport->dev,
UARTDM_RX_BUF_SIZE, 16, 0);
if (!rx->pool) {
pr_err("%s(): cannot allocate rx_buffer_pool", __func__);
ret = -ENOMEM;
goto err_dma_pool_create;
}
rx->buffer = dma_pool_alloc(rx->pool, GFP_KERNEL, &rx->rbuffer);
if (!rx->buffer) {
pr_err("%s(): cannot allocate rx->buffer", __func__);
ret = -ENOMEM;
goto err_dma_pool_alloc;
}
/* Allocate the command pointer. Needs to be 64 bit aligned */
rx->command_ptr = kmalloc(sizeof(dmov_box), GFP_KERNEL | __GFP_DMA);
if (!rx->command_ptr) {
pr_err("%s(): cannot allocate rx->command_ptr", __func__);
ret = -ENOMEM;
goto err_rx_command_ptr;
}
rx->command_ptr_ptr = kmalloc(sizeof(u32), GFP_KERNEL | __GFP_DMA);
if (!rx->command_ptr_ptr) {
pr_err("%s(): cannot allocate rx->command_ptr_ptr", __func__);
ret = -ENOMEM;
goto err_rx_command_ptr_ptr;
}
rx->command_ptr->num_rows = ((UARTDM_RX_BUF_SIZE >> 4) << 16) |
(UARTDM_RX_BUF_SIZE >> 4);
rx->command_ptr->dst_row_addr = rx->rbuffer;
rx->mapped_cmd_ptr = dma_map_single(uport->dev, rx->command_ptr,
sizeof(dmov_box), DMA_TO_DEVICE);
*rx->command_ptr_ptr = CMD_PTR_LP | DMOV_CMD_ADDR(rx->mapped_cmd_ptr);
rx->cmdptr_dmaaddr = dma_map_single(uport->dev, rx->command_ptr_ptr,
sizeof(u32), DMA_TO_DEVICE);
rx->xfer.cmdptr = DMOV_CMD_ADDR(rx->cmdptr_dmaaddr);
INIT_WORK(&rx->tty_work, msm_hs_tty_flip_buffer_work);
return ret;
err_rx_command_ptr_ptr:
kfree(rx->command_ptr);
err_rx_command_ptr:
dma_pool_free(msm_uport->rx.pool, msm_uport->rx.buffer,
msm_uport->rx.rbuffer);
err_dma_pool_alloc:
dma_pool_destroy(msm_uport->rx.pool);
err_dma_pool_create:
dma_unmap_single(uport->dev, msm_uport->tx.mapped_cmd_ptr_ptr,
sizeof(u32), DMA_TO_DEVICE);
dma_unmap_single(uport->dev, msm_uport->tx.mapped_cmd_ptr,
sizeof(dmov_box), DMA_TO_DEVICE);
kfree(msm_uport->tx.command_ptr_ptr);
err_tx_command_ptr_ptr:
kfree(msm_uport->tx.command_ptr);
return ret;
}
static int msm_hs_probe(struct platform_device *pdev)
{
int ret;
struct uart_port *uport;
struct msm_hs_port *msm_uport;
struct resource *resource;
const struct msm_serial_hs_platform_data *pdata =
dev_get_platdata(&pdev->dev);
if (pdev->id < 0 || pdev->id >= UARTDM_NR) {
printk(KERN_ERR "Invalid plaform device ID = %d\n", pdev->id);
return -EINVAL;
}
msm_uport = &q_uart_port[pdev->id];
uport = &msm_uport->uport;
uport->dev = &pdev->dev;
resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (unlikely(!resource))
return -ENXIO;
uport->mapbase = resource->start;
uport->irq = platform_get_irq(pdev, 0);
if (unlikely(uport->irq < 0))
return -ENXIO;
if (unlikely(irq_set_irq_wake(uport->irq, 1)))
return -ENXIO;
if (pdata == NULL || pdata->rx_wakeup_irq < 0)
msm_uport->rx_wakeup.irq = -1;
else {
msm_uport->rx_wakeup.irq = pdata->rx_wakeup_irq;
msm_uport->rx_wakeup.ignore = 1;
msm_uport->rx_wakeup.inject_rx = pdata->inject_rx_on_wakeup;
msm_uport->rx_wakeup.rx_to_inject = pdata->rx_to_inject;
if (unlikely(msm_uport->rx_wakeup.irq < 0))
return -ENXIO;
if (unlikely(irq_set_irq_wake(msm_uport->rx_wakeup.irq, 1)))
return -ENXIO;
}
if (pdata == NULL)
msm_uport->exit_lpm_cb = NULL;
else
msm_uport->exit_lpm_cb = pdata->exit_lpm_cb;
resource = platform_get_resource_byname(pdev, IORESOURCE_DMA,
"uartdm_channels");
if (unlikely(!resource))
return -ENXIO;
msm_uport->dma_tx_channel = resource->start;
msm_uport->dma_rx_channel = resource->end;
resource = platform_get_resource_byname(pdev, IORESOURCE_DMA,
"uartdm_crci");
if (unlikely(!resource))
return -ENXIO;
msm_uport->dma_tx_crci = resource->start;
msm_uport->dma_rx_crci = resource->end;
uport->iotype = UPIO_MEM;
uport->fifosize = UART_FIFOSIZE;
uport->ops = &msm_hs_ops;
uport->flags = UPF_BOOT_AUTOCONF;
uport->uartclk = UARTCLK;
msm_uport->imr_reg = 0x0;
msm_uport->clk = clk_get(&pdev->dev, "uartdm_clk");
if (IS_ERR(msm_uport->clk))
return PTR_ERR(msm_uport->clk);
ret = uartdm_init_port(uport);
if (unlikely(ret))
return ret;
msm_uport->clk_state = MSM_HS_CLK_PORT_OFF;
hrtimer_init(&msm_uport->clk_off_timer, CLOCK_MONOTONIC,
HRTIMER_MODE_REL);
msm_uport->clk_off_timer.function = msm_hs_clk_off_retry;
msm_uport->clk_off_delay = ktime_set(0, 1000000); /* 1ms */
uport->line = pdev->id;
return uart_add_one_port(&msm_hs_driver, uport);
}
static int __init msm_serial_hs_init(void)
{
int ret, i;
/* Init all UARTS as non-configured */
for (i = 0; i < UARTDM_NR; i++)
q_uart_port[i].uport.type = PORT_UNKNOWN;
msm_hs_workqueue = create_singlethread_workqueue("msm_serial_hs");
if (unlikely(!msm_hs_workqueue))
return -ENOMEM;
ret = uart_register_driver(&msm_hs_driver);
if (unlikely(ret)) {
printk(KERN_ERR "%s failed to load\n", __func__);
goto err_uart_register_driver;
}
ret = platform_driver_register(&msm_serial_hs_platform_driver);
if (ret) {
printk(KERN_ERR "%s failed to load\n", __func__);
goto err_platform_driver_register;
}
return ret;
err_platform_driver_register:
uart_unregister_driver(&msm_hs_driver);
err_uart_register_driver:
destroy_workqueue(msm_hs_workqueue);
return ret;
}
module_init(msm_serial_hs_init);
/*
* Called by the upper layer when port is closed.
* - Disables the port
* - Unhook the ISR
*/
static void msm_hs_shutdown(struct uart_port *uport)
{
unsigned long flags;
struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
BUG_ON(msm_uport->rx.flush < FLUSH_STOP);
spin_lock_irqsave(&uport->lock, flags);
clk_enable(msm_uport->clk);
/* Disable the transmitter */
msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_TX_DISABLE_BMSK);
/* Disable the receiver */
msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_RX_DISABLE_BMSK);
pm_runtime_disable(uport->dev);
pm_runtime_set_suspended(uport->dev);
/* Free the interrupt */
free_irq(uport->irq, msm_uport);
if (use_low_power_rx_wakeup(msm_uport))
free_irq(msm_uport->rx_wakeup.irq, msm_uport);
msm_uport->imr_reg = 0;
msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
wait_event(msm_uport->rx.wait, msm_uport->rx.flush == FLUSH_SHUTDOWN);
clk_disable(msm_uport->clk); /* to balance local clk_enable() */
if (msm_uport->clk_state != MSM_HS_CLK_OFF)
clk_disable(msm_uport->clk); /* to balance clk_state */
msm_uport->clk_state = MSM_HS_CLK_PORT_OFF;
dma_unmap_single(uport->dev, msm_uport->tx.dma_base,
UART_XMIT_SIZE, DMA_TO_DEVICE);
spin_unlock_irqrestore(&uport->lock, flags);
if (cancel_work_sync(&msm_uport->rx.tty_work))
msm_hs_tty_flip_buffer_work(&msm_uport->rx.tty_work);
}
static void __exit msm_serial_hs_exit(void)
{
flush_workqueue(msm_hs_workqueue);
destroy_workqueue(msm_hs_workqueue);
platform_driver_unregister(&msm_serial_hs_platform_driver);
uart_unregister_driver(&msm_hs_driver);
}
module_exit(msm_serial_hs_exit);
#ifdef CONFIG_PM_RUNTIME
static int msm_hs_runtime_idle(struct device *dev)
{
/*
* returning success from idle results in runtime suspend to be
* called
*/
return 0;
}
static int msm_hs_runtime_resume(struct device *dev)
{
struct platform_device *pdev = container_of(dev, struct
platform_device, dev);
struct msm_hs_port *msm_uport = &q_uart_port[pdev->id];
msm_hs_request_clock_on(&msm_uport->uport);
return 0;
}
static int msm_hs_runtime_suspend(struct device *dev)
{
struct platform_device *pdev = container_of(dev, struct
platform_device, dev);
struct msm_hs_port *msm_uport = &q_uart_port[pdev->id];
msm_hs_request_clock_off(&msm_uport->uport);
return 0;
}
#else
#define msm_hs_runtime_idle NULL
#define msm_hs_runtime_resume NULL
#define msm_hs_runtime_suspend NULL
#endif
static const struct dev_pm_ops msm_hs_dev_pm_ops = {
.runtime_suspend = msm_hs_runtime_suspend,
.runtime_resume = msm_hs_runtime_resume,
.runtime_idle = msm_hs_runtime_idle,
};
static struct platform_driver msm_serial_hs_platform_driver = {
.probe = msm_hs_probe,
.remove = msm_hs_remove,
.driver = {
.name = "msm_serial_hs",
.owner = THIS_MODULE,
.pm = &msm_hs_dev_pm_ops,
},
};
static struct uart_driver msm_hs_driver = {
.owner = THIS_MODULE,
.driver_name = "msm_serial_hs",
.dev_name = "ttyHS",
.nr = UARTDM_NR,
.cons = 0,
};
static struct uart_ops msm_hs_ops = {
.tx_empty = msm_hs_tx_empty,
.set_mctrl = msm_hs_set_mctrl_locked,
.get_mctrl = msm_hs_get_mctrl_locked,
.stop_tx = msm_hs_stop_tx_locked,
.start_tx = msm_hs_start_tx_locked,
.stop_rx = msm_hs_stop_rx_locked,
.enable_ms = msm_hs_enable_ms_locked,
.break_ctl = msm_hs_break_ctl,
.startup = msm_hs_startup,
.shutdown = msm_hs_shutdown,
.set_termios = msm_hs_set_termios,
.pm = msm_hs_pm,
.type = msm_hs_type,
.config_port = msm_hs_config_port,
.release_port = msm_hs_release_port,
.request_port = msm_hs_request_port,
};
MODULE_DESCRIPTION("High Speed UART Driver for the MSM chipset");
MODULE_VERSION("1.2");
MODULE_LICENSE("GPL v2");