// SPDX-License-Identifier: GPL-2.0+
/*
* Maxim (Dallas) MAX3107/8/9, MAX14830 serial driver
*
* Copyright (C) 2012-2016 Alexander Shiyan <[email protected]>
*
* Based on max3100.c, by Christian Pellegrin <[email protected]>
* Based on max3110.c, by Feng Tang <[email protected]>
* Based on max3107.c, by Aavamobile
*/
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/gpio/driver.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/property.h>
#include <linux/regmap.h>
#include <linux/serial_core.h>
#include <linux/serial.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/spi/spi.h>
#include <linux/uaccess.h>
#define MAX310X_NAME "max310x"
#define MAX310X_MAJOR 204
#define MAX310X_MINOR 209
#define MAX310X_UART_NRMAX 16
#define MAX310X_MAX_PORTS 4 /* Maximum number of UART ports per IC. */
/* MAX310X register definitions */
#define MAX310X_RHR_REG (0x00) /* RX FIFO */
#define MAX310X_THR_REG (0x00) /* TX FIFO */
#define MAX310X_IRQEN_REG (0x01) /* IRQ enable */
#define MAX310X_IRQSTS_REG (0x02) /* IRQ status */
#define MAX310X_LSR_IRQEN_REG (0x03) /* LSR IRQ enable */
#define MAX310X_LSR_IRQSTS_REG (0x04) /* LSR IRQ status */
#define MAX310X_REG_05 (0x05)
#define MAX310X_SPCHR_IRQEN_REG MAX310X_REG_05 /* Special char IRQ en */
#define MAX310X_SPCHR_IRQSTS_REG (0x06) /* Special char IRQ status */
#define MAX310X_STS_IRQEN_REG (0x07) /* Status IRQ enable */
#define MAX310X_STS_IRQSTS_REG (0x08) /* Status IRQ status */
#define MAX310X_MODE1_REG (0x09) /* MODE1 */
#define MAX310X_MODE2_REG (0x0a) /* MODE2 */
#define MAX310X_LCR_REG (0x0b) /* LCR */
#define MAX310X_RXTO_REG (0x0c) /* RX timeout */
#define MAX310X_HDPIXDELAY_REG (0x0d) /* Auto transceiver delays */
#define MAX310X_IRDA_REG (0x0e) /* IRDA settings */
#define MAX310X_FLOWLVL_REG (0x0f) /* Flow control levels */
#define MAX310X_FIFOTRIGLVL_REG (0x10) /* FIFO IRQ trigger levels */
#define MAX310X_TXFIFOLVL_REG (0x11) /* TX FIFO level */
#define MAX310X_RXFIFOLVL_REG (0x12) /* RX FIFO level */
#define MAX310X_FLOWCTRL_REG (0x13) /* Flow control */
#define MAX310X_XON1_REG (0x14) /* XON1 character */
#define MAX310X_XON2_REG (0x15) /* XON2 character */
#define MAX310X_XOFF1_REG (0x16) /* XOFF1 character */
#define MAX310X_XOFF2_REG (0x17) /* XOFF2 character */
#define MAX310X_GPIOCFG_REG (0x18) /* GPIO config */
#define MAX310X_GPIODATA_REG (0x19) /* GPIO data */
#define MAX310X_PLLCFG_REG (0x1a) /* PLL config */
#define MAX310X_BRGCFG_REG (0x1b) /* Baud rate generator conf */
#define MAX310X_BRGDIVLSB_REG (0x1c) /* Baud rate divisor LSB */
#define MAX310X_BRGDIVMSB_REG (0x1d) /* Baud rate divisor MSB */
#define MAX310X_CLKSRC_REG (0x1e) /* Clock source */
#define MAX310X_REG_1F (0x1f)
#define MAX310X_EXTREG_START (0x20) /* Only relevant in SPI mode. */
#define MAX310X_REVID_REG MAX310X_REG_1F /* Revision ID */
#define MAX310X_GLOBALIRQ_REG MAX310X_REG_1F /* Global IRQ (RO) */
#define MAX310X_GLOBALCMD_REG MAX310X_REG_1F /* Global Command (WO) */
/* Extended registers */
#define MAX310X_REVID_EXTREG (0x25) /* Revision ID
* (extended addressing space)
*/
/* IRQ register bits */
#define MAX310X_IRQ_LSR_BIT (1 << 0) /* LSR interrupt */
#define MAX310X_IRQ_SPCHR_BIT (1 << 1) /* Special char interrupt */
#define MAX310X_IRQ_STS_BIT (1 << 2) /* Status interrupt */
#define MAX310X_IRQ_RXFIFO_BIT (1 << 3) /* RX FIFO interrupt */
#define MAX310X_IRQ_TXFIFO_BIT (1 << 4) /* TX FIFO interrupt */
#define MAX310X_IRQ_TXEMPTY_BIT (1 << 5) /* TX FIFO empty interrupt */
#define MAX310X_IRQ_RXEMPTY_BIT (1 << 6) /* RX FIFO empty interrupt */
#define MAX310X_IRQ_CTS_BIT (1 << 7) /* CTS interrupt */
/* LSR register bits */
#define MAX310X_LSR_RXTO_BIT (1 << 0) /* RX timeout */
#define MAX310X_LSR_RXOVR_BIT (1 << 1) /* RX overrun */
#define MAX310X_LSR_RXPAR_BIT (1 << 2) /* RX parity error */
#define MAX310X_LSR_FRERR_BIT (1 << 3) /* Frame error */
#define MAX310X_LSR_RXBRK_BIT (1 << 4) /* RX break */
#define MAX310X_LSR_RXNOISE_BIT (1 << 5) /* RX noise */
#define MAX310X_LSR_CTS_BIT (1 << 7) /* CTS pin state */
/* Special character register bits */
#define MAX310X_SPCHR_XON1_BIT (1 << 0) /* XON1 character */
#define MAX310X_SPCHR_XON2_BIT (1 << 1) /* XON2 character */
#define MAX310X_SPCHR_XOFF1_BIT (1 << 2) /* XOFF1 character */
#define MAX310X_SPCHR_XOFF2_BIT (1 << 3) /* XOFF2 character */
#define MAX310X_SPCHR_BREAK_BIT (1 << 4) /* RX break */
#define MAX310X_SPCHR_MULTIDROP_BIT (1 << 5) /* 9-bit multidrop addr char */
/* Status register bits */
#define MAX310X_STS_GPIO0_BIT (1 << 0) /* GPIO 0 interrupt */
#define MAX310X_STS_GPIO1_BIT (1 << 1) /* GPIO 1 interrupt */
#define MAX310X_STS_GPIO2_BIT (1 << 2) /* GPIO 2 interrupt */
#define MAX310X_STS_GPIO3_BIT (1 << 3) /* GPIO 3 interrupt */
#define MAX310X_STS_CLKREADY_BIT (1 << 5) /* Clock ready */
#define MAX310X_STS_SLEEP_BIT (1 << 6) /* Sleep interrupt */
/* MODE1 register bits */
#define MAX310X_MODE1_RXDIS_BIT (1 << 0) /* RX disable */
#define MAX310X_MODE1_TXDIS_BIT (1 << 1) /* TX disable */
#define MAX310X_MODE1_TXHIZ_BIT (1 << 2) /* TX pin three-state */
#define MAX310X_MODE1_RTSHIZ_BIT (1 << 3) /* RTS pin three-state */
#define MAX310X_MODE1_TRNSCVCTRL_BIT (1 << 4) /* Transceiver ctrl enable */
#define MAX310X_MODE1_FORCESLEEP_BIT (1 << 5) /* Force sleep mode */
#define MAX310X_MODE1_AUTOSLEEP_BIT (1 << 6) /* Auto sleep enable */
#define MAX310X_MODE1_IRQSEL_BIT (1 << 7) /* IRQ pin enable */
/* MODE2 register bits */
#define MAX310X_MODE2_RST_BIT (1 << 0) /* Chip reset */
#define MAX310X_MODE2_FIFORST_BIT (1 << 1) /* FIFO reset */
#define MAX310X_MODE2_RXTRIGINV_BIT (1 << 2) /* RX FIFO INT invert */
#define MAX310X_MODE2_RXEMPTINV_BIT (1 << 3) /* RX FIFO empty INT invert */
#define MAX310X_MODE2_SPCHR_BIT (1 << 4) /* Special chr detect enable */
#define MAX310X_MODE2_LOOPBACK_BIT (1 << 5) /* Internal loopback enable */
#define MAX310X_MODE2_MULTIDROP_BIT (1 << 6) /* 9-bit multidrop enable */
#define MAX310X_MODE2_ECHOSUPR_BIT (1 << 7) /* ECHO suppression enable */
/* LCR register bits */
#define MAX310X_LCR_LENGTH0_BIT (1 << 0) /* Word length bit 0 */
#define MAX310X_LCR_LENGTH1_BIT (1 << 1) /* Word length bit 1
*
* Word length bits table:
* 00 -> 5 bit words
* 01 -> 6 bit words
* 10 -> 7 bit words
* 11 -> 8 bit words
*/
#define MAX310X_LCR_STOPLEN_BIT (1 << 2) /* STOP length bit
*
* STOP length bit table:
* 0 -> 1 stop bit
* 1 -> 1-1.5 stop bits if
* word length is 5,
* 2 stop bits otherwise
*/
#define MAX310X_LCR_PARITY_BIT (1 << 3) /* Parity bit enable */
#define MAX310X_LCR_EVENPARITY_BIT (1 << 4) /* Even parity bit enable */
#define MAX310X_LCR_FORCEPARITY_BIT (1 << 5) /* 9-bit multidrop parity */
#define MAX310X_LCR_TXBREAK_BIT (1 << 6) /* TX break enable */
#define MAX310X_LCR_RTS_BIT (1 << 7) /* RTS pin control */
/* IRDA register bits */
#define MAX310X_IRDA_IRDAEN_BIT (1 << 0) /* IRDA mode enable */
#define MAX310X_IRDA_SIR_BIT (1 << 1) /* SIR mode enable */
/* Flow control trigger level register masks */
#define MAX310X_FLOWLVL_HALT_MASK GENMASK(3, 0) /* Flow control halt level */
#define MAX310X_FLOWLVL_RES_MASK GENMASK(7, 4) /* Flow control resume level */
#define MAX310X_FLOWLVL_HALT(words) ((words / 8) & 0x0f)
#define MAX310X_FLOWLVL_RES(words) (((words / 8) & 0x0f) << 4)
/* FIFO interrupt trigger level register masks */
#define MAX310X_FIFOTRIGLVL_TX_MASK GENMASK(3, 0) /* TX FIFO trigger level */
#define MAX310X_FIFOTRIGLVL_RX_MASK GENMASK(7, 4) /* RX FIFO trigger level */
#define MAX310X_FIFOTRIGLVL_TX(words) ((words / 8) & 0x0f)
#define MAX310X_FIFOTRIGLVL_RX(words) (((words / 8) & 0x0f) << 4)
/* Flow control register bits */
#define MAX310X_FLOWCTRL_AUTORTS_BIT (1 << 0) /* Auto RTS flow ctrl enable */
#define MAX310X_FLOWCTRL_AUTOCTS_BIT (1 << 1) /* Auto CTS flow ctrl enable */
#define MAX310X_FLOWCTRL_GPIADDR_BIT (1 << 2) /* Enables that GPIO inputs
* are used in conjunction with
* XOFF2 for definition of
* special character
*/
#define MAX310X_FLOWCTRL_SWFLOWEN_BIT (1 << 3) /* Auto SW flow ctrl enable */
#define MAX310X_FLOWCTRL_SWFLOW0_BIT (1 << 4) /* SWFLOW bit 0 */
#define MAX310X_FLOWCTRL_SWFLOW1_BIT (1 << 5) /* SWFLOW bit 1
*
* SWFLOW bits 1 & 0 table:
* 00 -> no transmitter flow
* control
* 01 -> receiver compares
* XON2 and XOFF2
* and controls
* transmitter
* 10 -> receiver compares
* XON1 and XOFF1
* and controls
* transmitter
* 11 -> receiver compares
* XON1, XON2, XOFF1 and
* XOFF2 and controls
* transmitter
*/
#define MAX310X_FLOWCTRL_SWFLOW2_BIT (1 << 6) /* SWFLOW bit 2 */
#define MAX310X_FLOWCTRL_SWFLOW3_BIT (1 << 7) /* SWFLOW bit 3
*
* SWFLOW bits 3 & 2 table:
* 00 -> no received flow
* control
* 01 -> transmitter generates
* XON2 and XOFF2
* 10 -> transmitter generates
* XON1 and XOFF1
* 11 -> transmitter generates
* XON1, XON2, XOFF1 and
* XOFF2
*/
/* PLL configuration register masks */
#define MAX310X_PLLCFG_PREDIV_MASK GENMASK(5, 0) /* PLL predivision value */
#define MAX310X_PLLCFG_PLLFACTOR_MASK GENMASK(7, 6) /* PLL multiplication factor */
/* Baud rate generator configuration register bits */
#define MAX310X_BRGCFG_2XMODE_BIT (1 << 4) /* Double baud rate */
#define MAX310X_BRGCFG_4XMODE_BIT (1 << 5) /* Quadruple baud rate */
/* Clock source register bits */
#define MAX310X_CLKSRC_CRYST_BIT (1 << 1) /* Crystal osc enable */
#define MAX310X_CLKSRC_PLL_BIT (1 << 2) /* PLL enable */
#define MAX310X_CLKSRC_PLLBYP_BIT (1 << 3) /* PLL bypass */
#define MAX310X_CLKSRC_EXTCLK_BIT (1 << 4) /* External clock enable */
#define MAX310X_CLKSRC_CLK2RTS_BIT (1 << 7) /* Baud clk to RTS pin */
/* Global commands */
#define MAX310X_EXTREG_ENBL (0xce)
#define MAX310X_EXTREG_DSBL (0xcd)
/* Misc definitions */
#define MAX310X_FIFO_SIZE (128)
#define MAX310x_REV_MASK GENMASK(7, 3)
#define MAX310X_WRITE_BIT 0x80
/* Port startup definitions */
#define MAX310X_PORT_STARTUP_WAIT_RETRIES 20 /* Number of retries */
#define MAX310X_PORT_STARTUP_WAIT_DELAY_MS 10 /* Delay between retries */
/* Crystal-related definitions */
#define MAX310X_XTAL_WAIT_RETRIES 20 /* Number of retries */
#define MAX310X_XTAL_WAIT_DELAY_MS 10 /* Delay between retries */
/* MAX3107 specific */
#define MAX3107_REV_ID (0xa0)
/* MAX3109 specific */
#define MAX3109_REV_ID (0xc0)
/* MAX14830 specific */
#define MAX14830_BRGCFG_CLKDIS_BIT (1 << 6) /* Clock Disable */
#define MAX14830_REV_ID (0xb0)
struct max310x_if_cfg {
int (*extended_reg_enable)(struct device *dev, bool enable);
u8 rev_id_offset;
};
struct max310x_devtype {
struct {
unsigned short min;
unsigned short max;
} slave_addr; /* Relevant only in I2C mode. */
int nr;
char name[9];
u8 mode1;
u8 rev_id_val;
u8 rev_id_reg; /* Relevant only if rev_id_val is defined. */
u8 power_reg; /* Register address for power/sleep control. */
u8 power_bit; /* Bit for sleep or power-off mode (active high). */
};
struct max310x_one {
struct uart_port port;
struct work_struct tx_work;
struct work_struct md_work;
struct work_struct rs_work;
struct regmap *regmap;
u8 rx_buf[MAX310X_FIFO_SIZE];
};
#define to_max310x_port(_port) \
container_of(_port, struct max310x_one, port)
struct max310x_port {
const struct max310x_devtype *devtype;
const struct max310x_if_cfg *if_cfg;
struct regmap *regmap;
struct clk *clk;
#ifdef CONFIG_GPIOLIB
struct gpio_chip gpio;
#endif
struct max310x_one p[];
};
static struct uart_driver max310x_uart = {
.owner = THIS_MODULE,
.driver_name = MAX310X_NAME,
.dev_name = "ttyMAX",
.major = MAX310X_MAJOR,
.minor = MAX310X_MINOR,
.nr = MAX310X_UART_NRMAX,
};
static DECLARE_BITMAP(max310x_lines, MAX310X_UART_NRMAX);
static u8 max310x_port_read(struct uart_port *port, u8 reg)
{
struct max310x_one *one = to_max310x_port(port);
unsigned int val = 0;
regmap_read(one->regmap, reg, &val);
return val;
}
static void max310x_port_write(struct uart_port *port, u8 reg, u8 val)
{
struct max310x_one *one = to_max310x_port(port);
regmap_write(one->regmap, reg, val);
}
static void max310x_port_update(struct uart_port *port, u8 reg, u8 mask, u8 val)
{
struct max310x_one *one = to_max310x_port(port);
regmap_update_bits(one->regmap, reg, mask, val);
}
static int max310x_detect(struct device *dev)
{
struct max310x_port *s = dev_get_drvdata(dev);
unsigned int val = 0;
int ret;
/* Check if variant supports REV ID register: */
if (s->devtype->rev_id_val) {
u8 rev_id_reg = s->devtype->rev_id_reg;
/* Check if REV ID is in extended addressing space: */
if (s->devtype->rev_id_reg >= MAX310X_EXTREG_START) {
ret = s->if_cfg->extended_reg_enable(dev, true);
if (ret)
return ret;
/* Adjust REV ID extended addressing space address: */
if (s->if_cfg->rev_id_offset)
rev_id_reg -= s->if_cfg->rev_id_offset;
}
regmap_read(s->regmap, rev_id_reg, &val);
if (s->devtype->rev_id_reg >= MAX310X_EXTREG_START) {
ret = s->if_cfg->extended_reg_enable(dev, false);
if (ret)
return ret;
}
if (((val & MAX310x_REV_MASK) != s->devtype->rev_id_val))
return dev_err_probe(dev, -ENODEV,
"%s ID 0x%02x does not match\n",
s->devtype->name, val);
} else {
/*
* For variant without REV ID register, just check default value
* from clocksource register to make sure everything works.
*/
ret = regmap_read(s->regmap, MAX310X_CLKSRC_REG, &val);
if (ret)
return ret;
if (val != (MAX310X_CLKSRC_EXTCLK_BIT | MAX310X_CLKSRC_PLLBYP_BIT))
return dev_err_probe(dev, -ENODEV,
"%s not present\n",
s->devtype->name);
}
return 0;
}
static void max310x_power(struct uart_port *port, int on)
{
struct max310x_port *s = dev_get_drvdata(port->dev);
max310x_port_update(port, s->devtype->power_reg, s->devtype->power_bit,
on ? 0 : s->devtype->power_bit);
if (on)
msleep(50);
}
static const struct max310x_devtype max3107_devtype = {
.name = "MAX3107",
.nr = 1,
.mode1 = MAX310X_MODE1_AUTOSLEEP_BIT | MAX310X_MODE1_IRQSEL_BIT,
.rev_id_val = MAX3107_REV_ID,
.rev_id_reg = MAX310X_REVID_REG,
.power_reg = MAX310X_MODE1_REG,
.power_bit = MAX310X_MODE1_FORCESLEEP_BIT,
.slave_addr = {
.min = 0x2c,
.max = 0x2f,
},
};
static const struct max310x_devtype max3108_devtype = {
.name = "MAX3108",
.nr = 1,
.mode1 = MAX310X_MODE1_AUTOSLEEP_BIT,
.rev_id_val = 0, /* Unsupported. */
.rev_id_reg = 0, /* Irrelevant when rev_id_val is not defined. */
.power_reg = MAX310X_MODE1_REG,
.power_bit = MAX310X_MODE1_FORCESLEEP_BIT,
.slave_addr = {
.min = 0x60,
.max = 0x6f,
},
};
static const struct max310x_devtype max3109_devtype = {
.name = "MAX3109",
.nr = 2,
.mode1 = MAX310X_MODE1_AUTOSLEEP_BIT,
.rev_id_val = MAX3109_REV_ID,
.rev_id_reg = MAX310X_REVID_EXTREG,
.power_reg = MAX310X_MODE1_REG,
.power_bit = MAX310X_MODE1_FORCESLEEP_BIT,
.slave_addr = {
.min = 0x60,
.max = 0x6f,
},
};
static const struct max310x_devtype max14830_devtype = {
.name = "MAX14830",
.nr = 4,
.mode1 = MAX310X_MODE1_IRQSEL_BIT,
.rev_id_val = MAX14830_REV_ID,
.rev_id_reg = MAX310X_REVID_EXTREG,
.power_reg = MAX310X_BRGCFG_REG,
.power_bit = MAX14830_BRGCFG_CLKDIS_BIT,
.slave_addr = {
.min = 0x60,
.max = 0x6f,
},
};
static bool max310x_reg_writeable(struct device *dev, unsigned int reg)
{
switch (reg) {
case MAX310X_IRQSTS_REG:
case MAX310X_LSR_IRQSTS_REG:
case MAX310X_SPCHR_IRQSTS_REG:
case MAX310X_STS_IRQSTS_REG:
case MAX310X_TXFIFOLVL_REG:
case MAX310X_RXFIFOLVL_REG:
return false;
default:
return true;
}
}
static bool max310x_reg_volatile(struct device *dev, unsigned int reg)
{
switch (reg) {
case MAX310X_RHR_REG:
case MAX310X_IRQSTS_REG:
case MAX310X_LSR_IRQSTS_REG:
case MAX310X_SPCHR_IRQSTS_REG:
case MAX310X_STS_IRQSTS_REG:
case MAX310X_TXFIFOLVL_REG:
case MAX310X_RXFIFOLVL_REG:
case MAX310X_GPIODATA_REG:
case MAX310X_BRGDIVLSB_REG:
case MAX310X_REG_05:
case MAX310X_REG_1F:
return true;
default:
return false;
}
}
static bool max310x_reg_precious(struct device *dev, unsigned int reg)
{
switch (reg) {
case MAX310X_RHR_REG:
case MAX310X_IRQSTS_REG:
case MAX310X_SPCHR_IRQSTS_REG:
case MAX310X_STS_IRQSTS_REG:
return true;
default:
return false;
}
}
static bool max310x_reg_noinc(struct device *dev, unsigned int reg)
{
return reg == MAX310X_RHR_REG;
}
static int max310x_set_baud(struct uart_port *port, int baud)
{
unsigned int mode = 0, div = 0, frac = 0, c = 0, F = 0;
/*
* Calculate the integer divisor first. Select a proper mode
* in case if the requested baud is too high for the pre-defined
* clocks frequency.
*/
div = port->uartclk / baud;
if (div < 8) {
/* Mode x4 */
c = 4;
mode = MAX310X_BRGCFG_4XMODE_BIT;
} else if (div < 16) {
/* Mode x2 */
c = 8;
mode = MAX310X_BRGCFG_2XMODE_BIT;
} else {
c = 16;
}
/* Calculate the divisor in accordance with the fraction coefficient */
div /= c;
F = c*baud;
/* Calculate the baud rate fraction */
if (div > 0)
frac = (16*(port->uartclk % F)) / F;
else
div = 1;
max310x_port_write(port, MAX310X_BRGDIVMSB_REG, div >> 8);
max310x_port_write(port, MAX310X_BRGDIVLSB_REG, div);
max310x_port_write(port, MAX310X_BRGCFG_REG, frac | mode);
/* Return the actual baud rate we just programmed */
return (16*port->uartclk) / (c*(16*div + frac));
}
static int max310x_update_best_err(unsigned long f, long *besterr)
{
/* Use baudrate 115200 for calculate error */
long err = f % (460800 * 16);
if ((*besterr < 0) || (*besterr > err)) {
*besterr = err;
return 0;
}
return 1;
}
static s32 max310x_set_ref_clk(struct device *dev, struct max310x_port *s,
unsigned long freq, bool xtal)
{
unsigned int div, clksrc, pllcfg = 0;
long besterr = -1;
unsigned long fdiv, fmul, bestfreq = freq;
/* First, update error without PLL */
max310x_update_best_err(freq, &besterr);
/* Try all possible PLL dividers */
for (div = 1; (div <= 63) && besterr; div++) {
fdiv = DIV_ROUND_CLOSEST(freq, div);
/* Try multiplier 6 */
fmul = fdiv * 6;
if ((fdiv >= 500000) && (fdiv <= 800000))
if (!max310x_update_best_err(fmul, &besterr)) {
pllcfg = (0 << 6) | div;
bestfreq = fmul;
}
/* Try multiplier 48 */
fmul = fdiv * 48;
if ((fdiv >= 850000) && (fdiv <= 1200000))
if (!max310x_update_best_err(fmul, &besterr)) {
pllcfg = (1 << 6) | div;
bestfreq = fmul;
}
/* Try multiplier 96 */
fmul = fdiv * 96;
if ((fdiv >= 425000) && (fdiv <= 1000000))
if (!max310x_update_best_err(fmul, &besterr)) {
pllcfg = (2 << 6) | div;
bestfreq = fmul;
}
/* Try multiplier 144 */
fmul = fdiv * 144;
if ((fdiv >= 390000) && (fdiv <= 667000))
if (!max310x_update_best_err(fmul, &besterr)) {
pllcfg = (3 << 6) | div;
bestfreq = fmul;
}
}
/* Configure clock source */
clksrc = MAX310X_CLKSRC_EXTCLK_BIT | (xtal ? MAX310X_CLKSRC_CRYST_BIT : 0);
/* Configure PLL */
if (pllcfg) {
clksrc |= MAX310X_CLKSRC_PLL_BIT;
regmap_write(s->regmap, MAX310X_PLLCFG_REG, pllcfg);
} else
clksrc |= MAX310X_CLKSRC_PLLBYP_BIT;
regmap_write(s->regmap, MAX310X_CLKSRC_REG, clksrc);
/* Wait for crystal */
if (xtal) {
bool stable = false;
unsigned int try = 0, val = 0;
do {
msleep(MAX310X_XTAL_WAIT_DELAY_MS);
regmap_read(s->regmap, MAX310X_STS_IRQSTS_REG, &val);
if (val & MAX310X_STS_CLKREADY_BIT)
stable = true;
} while (!stable && (++try < MAX310X_XTAL_WAIT_RETRIES));
if (!stable)
return dev_err_probe(dev, -EAGAIN,
"clock is not stable\n");
}
return bestfreq;
}
static void max310x_batch_write(struct uart_port *port, u8 *txbuf, unsigned int len)
{
struct max310x_one *one = to_max310x_port(port);
regmap_noinc_write(one->regmap, MAX310X_THR_REG, txbuf, len);
}
static void max310x_batch_read(struct uart_port *port, u8 *rxbuf, unsigned int len)
{
struct max310x_one *one = to_max310x_port(port);
regmap_noinc_read(one->regmap, MAX310X_RHR_REG, rxbuf, len);
}
static void max310x_handle_rx(struct uart_port *port, unsigned int rxlen)
{
struct max310x_one *one = to_max310x_port(port);
unsigned int sts, i;
u8 ch, flag;
if (port->read_status_mask == MAX310X_LSR_RXOVR_BIT) {
/*
* We are just reading, happily ignoring any error conditions.
* Break condition, parity checking, framing errors -- they
* are all ignored. That means that we can do a batch-read.
*
* There is a small opportunity for race if the RX FIFO
* overruns while we're reading the buffer; the datasheets says
* that the LSR register applies to the "current" character.
* That's also the reason why we cannot do batched reads when
* asked to check the individual statuses.
*/
sts = max310x_port_read(port, MAX310X_LSR_IRQSTS_REG);
max310x_batch_read(port, one->rx_buf, rxlen);
port->icount.rx += rxlen;
flag = TTY_NORMAL;
sts &= port->read_status_mask;
if (sts & MAX310X_LSR_RXOVR_BIT) {
dev_warn_ratelimited(port->dev, "Hardware RX FIFO overrun\n");
port->icount.overrun++;
}
for (i = 0; i < (rxlen - 1); ++i)
uart_insert_char(port, sts, 0, one->rx_buf[i], flag);
/*
* Handle the overrun case for the last character only, since
* the RxFIFO overflow happens after it is pushed to the FIFO
* tail.
*/
uart_insert_char(port, sts, MAX310X_LSR_RXOVR_BIT,
one->rx_buf[rxlen-1], flag);
} else {
if (unlikely(rxlen >= port->fifosize)) {
dev_warn_ratelimited(port->dev, "Possible RX FIFO overrun\n");
port->icount.buf_overrun++;
/* Ensure sanity of RX level */
rxlen = port->fifosize;
}
while (rxlen--) {
ch = max310x_port_read(port, MAX310X_RHR_REG);
sts = max310x_port_read(port, MAX310X_LSR_IRQSTS_REG);
sts &= MAX310X_LSR_RXPAR_BIT | MAX310X_LSR_FRERR_BIT |
MAX310X_LSR_RXOVR_BIT | MAX310X_LSR_RXBRK_BIT;
port->icount.rx++;
flag = TTY_NORMAL;
if (unlikely(sts)) {
if (sts & MAX310X_LSR_RXBRK_BIT) {
port->icount.brk++;
if (uart_handle_break(port))
continue;
} else if (sts & MAX310X_LSR_RXPAR_BIT)
port->icount.parity++;
else if (sts & MAX310X_LSR_FRERR_BIT)
port->icount.frame++;
else if (sts & MAX310X_LSR_RXOVR_BIT)
port->icount.overrun++;
sts &= port->read_status_mask;
if (sts & MAX310X_LSR_RXBRK_BIT)
flag = TTY_BREAK;
else if (sts & MAX310X_LSR_RXPAR_BIT)
flag = TTY_PARITY;
else if (sts & MAX310X_LSR_FRERR_BIT)
flag = TTY_FRAME;
else if (sts & MAX310X_LSR_RXOVR_BIT)
flag = TTY_OVERRUN;
}
if (uart_handle_sysrq_char(port, ch))
continue;
if (sts & port->ignore_status_mask)
continue;
uart_insert_char(port, sts, MAX310X_LSR_RXOVR_BIT, ch, flag);
}
}
tty_flip_buffer_push(&port->state->port);
}
static void max310x_handle_tx(struct uart_port *port)
{
struct tty_port *tport = &port->state->port;
unsigned int txlen, to_send;
unsigned char *tail;
if (unlikely(port->x_char)) {
max310x_port_write(port, MAX310X_THR_REG, port->x_char);
port->icount.tx++;
port->x_char = 0;
return;
}
if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port))
return;
/*
* It's a circ buffer -- wrap around.
* We could do that in one SPI transaction, but meh.
*/
while (!kfifo_is_empty(&tport->xmit_fifo)) {
/* Limit to space available in TX FIFO */
txlen = max310x_port_read(port, MAX310X_TXFIFOLVL_REG);
txlen = port->fifosize - txlen;
if (!txlen)
break;
to_send = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, txlen);
max310x_batch_write(port, tail, to_send);
uart_xmit_advance(port, to_send);
}
if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
uart_write_wakeup(port);
}
static void max310x_start_tx(struct uart_port *port)
{
struct max310x_one *one = to_max310x_port(port);
schedule_work(&one->tx_work);
}
static irqreturn_t max310x_port_irq(struct max310x_port *s, int portno)
{
struct uart_port *port = &s->p[portno].port;
irqreturn_t res = IRQ_NONE;
do {
unsigned int ists, lsr, rxlen;
/* Read IRQ status & RX FIFO level */
ists = max310x_port_read(port, MAX310X_IRQSTS_REG);
rxlen = max310x_port_read(port, MAX310X_RXFIFOLVL_REG);
if (!ists && !rxlen)
break;
res = IRQ_HANDLED;
if (ists & MAX310X_IRQ_CTS_BIT) {
lsr = max310x_port_read(port, MAX310X_LSR_IRQSTS_REG);
uart_handle_cts_change(port, lsr & MAX310X_LSR_CTS_BIT);
}
if (rxlen)
max310x_handle_rx(port, rxlen);
if (ists & MAX310X_IRQ_TXEMPTY_BIT)
max310x_start_tx(port);
} while (1);
return res;
}
static irqreturn_t max310x_ist(int irq, void *dev_id)
{
struct max310x_port *s = (struct max310x_port *)dev_id;
bool handled = false;
if (s->devtype->nr > 1) {
do {
unsigned int val = ~0;
WARN_ON_ONCE(regmap_read(s->regmap,
MAX310X_GLOBALIRQ_REG, &val));
val = ((1 << s->devtype->nr) - 1) & ~val;
if (!val)
break;
if (max310x_port_irq(s, fls(val) - 1) == IRQ_HANDLED)
handled = true;
} while (1);
} else {
if (max310x_port_irq(s, 0) == IRQ_HANDLED)
handled = true;
}
return IRQ_RETVAL(handled);
}
static void max310x_tx_proc(struct work_struct *ws)
{
struct max310x_one *one = container_of(ws, struct max310x_one, tx_work);
max310x_handle_tx(&one->port);
}
static unsigned int max310x_tx_empty(struct uart_port *port)
{
u8 lvl = max310x_port_read(port, MAX310X_TXFIFOLVL_REG);
return lvl ? 0 : TIOCSER_TEMT;
}
static unsigned int max310x_get_mctrl(struct uart_port *port)
{
/*
* DCD and DSR are not wired and CTS/RTS is handled automatically
* so just indicate DSR and CAR asserted
*/
return TIOCM_DSR | TIOCM_CAR;
}
static void max310x_md_proc(struct work_struct *ws)
{
struct max310x_one *one = container_of(ws, struct max310x_one, md_work);
max310x_port_update(&one->port, MAX310X_MODE2_REG,
MAX310X_MODE2_LOOPBACK_BIT,
(one->port.mctrl & TIOCM_LOOP) ?
MAX310X_MODE2_LOOPBACK_BIT : 0);
}
static void max310x_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct max310x_one *one = to_max310x_port(port);
schedule_work(&one->md_work);
}
static void max310x_break_ctl(struct uart_port *port, int break_state)
{
max310x_port_update(port, MAX310X_LCR_REG,
MAX310X_LCR_TXBREAK_BIT,
break_state ? MAX310X_LCR_TXBREAK_BIT : 0);
}
static void max310x_set_termios(struct uart_port *port,
struct ktermios *termios,
const struct ktermios *old)
{
unsigned int lcr = 0, flow = 0;
int baud;
/* Mask termios capabilities we don't support */
termios->c_cflag &= ~CMSPAR;
/* Word size */
switch (termios->c_cflag & CSIZE) {
case CS5:
break;
case CS6:
lcr = MAX310X_LCR_LENGTH0_BIT;
break;
case CS7:
lcr = MAX310X_LCR_LENGTH1_BIT;
break;
case CS8:
default:
lcr = MAX310X_LCR_LENGTH1_BIT | MAX310X_LCR_LENGTH0_BIT;
break;
}
/* Parity */
if (termios->c_cflag & PARENB) {
lcr |= MAX310X_LCR_PARITY_BIT;
if (!(termios->c_cflag & PARODD))
lcr |= MAX310X_LCR_EVENPARITY_BIT;
}
/* Stop bits */
if (termios->c_cflag & CSTOPB)
lcr |= MAX310X_LCR_STOPLEN_BIT; /* 2 stops */
/* Update LCR register */
max310x_port_write(port, MAX310X_LCR_REG, lcr);
/* Set read status mask */
port->read_status_mask = MAX310X_LSR_RXOVR_BIT;
if (termios->c_iflag & INPCK)
port->read_status_mask |= MAX310X_LSR_RXPAR_BIT |
MAX310X_LSR_FRERR_BIT;
if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
port->read_status_mask |= MAX310X_LSR_RXBRK_BIT;
/* Set status ignore mask */
port->ignore_status_mask = 0;
if (termios->c_iflag & IGNBRK)
port->ignore_status_mask |= MAX310X_LSR_RXBRK_BIT;
if (!(termios->c_cflag & CREAD))
port->ignore_status_mask |= MAX310X_LSR_RXPAR_BIT |
MAX310X_LSR_RXOVR_BIT |
MAX310X_LSR_FRERR_BIT |
MAX310X_LSR_RXBRK_BIT;
/* Configure flow control */
max310x_port_write(port, MAX310X_XON1_REG, termios->c_cc[VSTART]);
max310x_port_write(port, MAX310X_XOFF1_REG, termios->c_cc[VSTOP]);
/*
* Disable transmitter before enabling AutoCTS or auto transmitter
* flow control
*/
if (termios->c_cflag & CRTSCTS || termios->c_iflag & IXOFF) {
max310x_port_update(port, MAX310X_MODE1_REG,
MAX310X_MODE1_TXDIS_BIT,
MAX310X_MODE1_TXDIS_BIT);
}
port->status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
if (termios->c_cflag & CRTSCTS) {
/* Enable AUTORTS and AUTOCTS */
port->status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
flow |= MAX310X_FLOWCTRL_AUTOCTS_BIT |
MAX310X_FLOWCTRL_AUTORTS_BIT;
}
if (termios->c_iflag & IXON)
flow |= MAX310X_FLOWCTRL_SWFLOW3_BIT |
MAX310X_FLOWCTRL_SWFLOWEN_BIT;
if (termios->c_iflag & IXOFF) {
port->status |= UPSTAT_AUTOXOFF;
flow |= MAX310X_FLOWCTRL_SWFLOW1_BIT |
MAX310X_FLOWCTRL_SWFLOWEN_BIT;
}
max310x_port_write(port, MAX310X_FLOWCTRL_REG, flow);
/*
* Enable transmitter after disabling AutoCTS and auto transmitter
* flow control
*/
if (!(termios->c_cflag & CRTSCTS) && !(termios->c_iflag & IXOFF)) {
max310x_port_update(port, MAX310X_MODE1_REG,
MAX310X_MODE1_TXDIS_BIT,
0);
}
/* Get baud rate generator configuration */
baud = uart_get_baud_rate(port, termios, old,
port->uartclk / 16 / 0xffff,
port->uartclk / 4);
/* Setup baudrate generator */
baud = max310x_set_baud(port, baud);
/* Update timeout according to new baud rate */
uart_update_timeout(port, termios->c_cflag, baud);
}
static void max310x_rs_proc(struct work_struct *ws)
{
struct max310x_one *one = container_of(ws, struct max310x_one, rs_work);
unsigned int delay, mode1 = 0, mode2 = 0;
delay = (one->port.rs485.delay_rts_before_send << 4) |
one->port.rs485.delay_rts_after_send;
max310x_port_write(&one->port, MAX310X_HDPIXDELAY_REG, delay);
if (one->port.rs485.flags & SER_RS485_ENABLED) {
mode1 = MAX310X_MODE1_TRNSCVCTRL_BIT;
if (!(one->port.rs485.flags & SER_RS485_RX_DURING_TX))
mode2 = MAX310X_MODE2_ECHOSUPR_BIT;
}
max310x_port_update(&one->port, MAX310X_MODE1_REG,
MAX310X_MODE1_TRNSCVCTRL_BIT, mode1);
max310x_port_update(&one->port, MAX310X_MODE2_REG,
MAX310X_MODE2_ECHOSUPR_BIT, mode2);
}
static int max310x_rs485_config(struct uart_port *port, struct ktermios *termios,
struct serial_rs485 *rs485)
{
struct max310x_one *one = to_max310x_port(port);
if ((rs485->delay_rts_before_send > 0x0f) ||
(rs485->delay_rts_after_send > 0x0f))
return -ERANGE;
port->rs485 = *rs485;
schedule_work(&one->rs_work);
return 0;
}
static int max310x_startup(struct uart_port *port)
{
unsigned int val;
max310x_power(port, 1);
/* Configure MODE1 register */
max310x_port_update(port, MAX310X_MODE1_REG,
MAX310X_MODE1_TRNSCVCTRL_BIT, 0);
/* Configure MODE2 register & Reset FIFOs*/
val = MAX310X_MODE2_RXEMPTINV_BIT | MAX310X_MODE2_FIFORST_BIT;
max310x_port_write(port, MAX310X_MODE2_REG, val);
max310x_port_update(port, MAX310X_MODE2_REG,
MAX310X_MODE2_FIFORST_BIT, 0);
/* Configure mode1/mode2 to have rs485/rs232 enabled at startup */
val = (clamp(port->rs485.delay_rts_before_send, 0U, 15U) << 4) |
clamp(port->rs485.delay_rts_after_send, 0U, 15U);
max310x_port_write(port, MAX310X_HDPIXDELAY_REG, val);
if (port->rs485.flags & SER_RS485_ENABLED) {
max310x_port_update(port, MAX310X_MODE1_REG,
MAX310X_MODE1_TRNSCVCTRL_BIT,
MAX310X_MODE1_TRNSCVCTRL_BIT);
if (!(port->rs485.flags & SER_RS485_RX_DURING_TX))
max310x_port_update(port, MAX310X_MODE2_REG,
MAX310X_MODE2_ECHOSUPR_BIT,
MAX310X_MODE2_ECHOSUPR_BIT);
}
/*
* Configure flow control levels:
* resume: 48
* halt: 96
*/
max310x_port_write(port, MAX310X_FLOWLVL_REG,
MAX310X_FLOWLVL_RES(48) | MAX310X_FLOWLVL_HALT(96));
/* Clear IRQ status register */
max310x_port_read(port, MAX310X_IRQSTS_REG);
/* Enable RX, TX, CTS change interrupts */
val = MAX310X_IRQ_RXEMPTY_BIT | MAX310X_IRQ_TXEMPTY_BIT;
max310x_port_write(port, MAX310X_IRQEN_REG, val | MAX310X_IRQ_CTS_BIT);
return 0;
}
static void max310x_shutdown(struct uart_port *port)
{
/* Disable all interrupts */
max310x_port_write(port, MAX310X_IRQEN_REG, 0);
max310x_power(port, 0);
}
static const char *max310x_type(struct uart_port *port)
{
struct max310x_port *s = dev_get_drvdata(port->dev);
return (port->type == PORT_MAX310X) ? s->devtype->name : NULL;
}
static int max310x_request_port(struct uart_port *port)
{
/* Do nothing */
return 0;
}
static void max310x_config_port(struct uart_port *port, int flags)
{
if (flags & UART_CONFIG_TYPE)
port->type = PORT_MAX310X;
}
static int max310x_verify_port(struct uart_port *port, struct serial_struct *s)
{
if ((s->type != PORT_UNKNOWN) && (s->type != PORT_MAX310X))
return -EINVAL;
if (s->irq != port->irq)
return -EINVAL;
return 0;
}
static void max310x_null_void(struct uart_port *port)
{
/* Do nothing */
}
static const struct uart_ops max310x_ops = {
.tx_empty = max310x_tx_empty,
.set_mctrl = max310x_set_mctrl,
.get_mctrl = max310x_get_mctrl,
.stop_tx = max310x_null_void,
.start_tx = max310x_start_tx,
.stop_rx = max310x_null_void,
.break_ctl = max310x_break_ctl,
.startup = max310x_startup,
.shutdown = max310x_shutdown,
.set_termios = max310x_set_termios,
.type = max310x_type,
.request_port = max310x_request_port,
.release_port = max310x_null_void,
.config_port = max310x_config_port,
.verify_port = max310x_verify_port,
};
static int __maybe_unused max310x_suspend(struct device *dev)
{
struct max310x_port *s = dev_get_drvdata(dev);
int i;
for (i = 0; i < s->devtype->nr; i++) {
uart_suspend_port(&max310x_uart, &s->p[i].port);
max310x_power(&s->p[i].port, 0);
}
return 0;
}
static int __maybe_unused max310x_resume(struct device *dev)
{
struct max310x_port *s = dev_get_drvdata(dev);
int i;
for (i = 0; i < s->devtype->nr; i++) {
max310x_power(&s->p[i].port, 1);
uart_resume_port(&max310x_uart, &s->p[i].port);
}
return 0;
}
static SIMPLE_DEV_PM_OPS(max310x_pm_ops, max310x_suspend, max310x_resume);
#ifdef CONFIG_GPIOLIB
static int max310x_gpio_get(struct gpio_chip *chip, unsigned int offset)
{
unsigned int val;
struct max310x_port *s = gpiochip_get_data(chip);
struct uart_port *port = &s->p[offset / 4].port;
val = max310x_port_read(port, MAX310X_GPIODATA_REG);
return !!((val >> 4) & (1 << (offset % 4)));
}
static void max310x_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
{
struct max310x_port *s = gpiochip_get_data(chip);
struct uart_port *port = &s->p[offset / 4].port;
max310x_port_update(port, MAX310X_GPIODATA_REG, 1 << (offset % 4),
value ? 1 << (offset % 4) : 0);
}
static int max310x_gpio_direction_input(struct gpio_chip *chip, unsigned int offset)
{
struct max310x_port *s = gpiochip_get_data(chip);
struct uart_port *port = &s->p[offset / 4].port;
max310x_port_update(port, MAX310X_GPIOCFG_REG, 1 << (offset % 4), 0);
return 0;
}
static int max310x_gpio_direction_output(struct gpio_chip *chip,
unsigned int offset, int value)
{
struct max310x_port *s = gpiochip_get_data(chip);
struct uart_port *port = &s->p[offset / 4].port;
max310x_port_update(port, MAX310X_GPIODATA_REG, 1 << (offset % 4),
value ? 1 << (offset % 4) : 0);
max310x_port_update(port, MAX310X_GPIOCFG_REG, 1 << (offset % 4),
1 << (offset % 4));
return 0;
}
static int max310x_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
unsigned long config)
{
struct max310x_port *s = gpiochip_get_data(chip);
struct uart_port *port = &s->p[offset / 4].port;
switch (pinconf_to_config_param(config)) {
case PIN_CONFIG_DRIVE_OPEN_DRAIN:
max310x_port_update(port, MAX310X_GPIOCFG_REG,
1 << ((offset % 4) + 4),
1 << ((offset % 4) + 4));
return 0;
case PIN_CONFIG_DRIVE_PUSH_PULL:
max310x_port_update(port, MAX310X_GPIOCFG_REG,
1 << ((offset % 4) + 4), 0);
return 0;
default:
return -ENOTSUPP;
}
}
#endif
static const struct serial_rs485 max310x_rs485_supported = {
.flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RX_DURING_TX,
.delay_rts_before_send = 1,
.delay_rts_after_send = 1,
};
static int max310x_probe(struct device *dev, const struct max310x_devtype *devtype,
const struct max310x_if_cfg *if_cfg,
struct regmap *regmaps[], int irq)
{
int i, ret, fmin, fmax, freq;
struct max310x_port *s;
s32 uartclk = 0;
bool xtal;
for (i = 0; i < devtype->nr; i++)
if (IS_ERR(regmaps[i]))
return PTR_ERR(regmaps[i]);
/* Alloc port structure */
s = devm_kzalloc(dev, struct_size(s, p, devtype->nr), GFP_KERNEL);
if (!s)
return dev_err_probe(dev, -ENOMEM,
"Error allocating port structure\n");
/* Always ask for fixed clock rate from a property. */
device_property_read_u32(dev, "clock-frequency", &uartclk);
xtal = device_property_match_string(dev, "clock-names", "osc") < 0;
if (xtal)
s->clk = devm_clk_get_optional(dev, "xtal");
else
s->clk = devm_clk_get_optional(dev, "osc");
if (IS_ERR(s->clk))
return PTR_ERR(s->clk);
ret = clk_prepare_enable(s->clk);
if (ret)
return ret;
freq = clk_get_rate(s->clk);
if (freq == 0)
freq = uartclk;
if (freq == 0) {
ret = dev_err_probe(dev, -EINVAL, "Cannot get clock rate\n");
goto out_clk;
}
if (xtal) {
fmin = 1000000;
fmax = 4000000;
} else {
fmin = 500000;
fmax = 35000000;
}
/* Check frequency limits */
if (freq < fmin || freq > fmax) {
ret = -ERANGE;
goto out_clk;
}
s->regmap = regmaps[0];
s->devtype = devtype;
s->if_cfg = if_cfg;
dev_set_drvdata(dev, s);
/* Check device to ensure we are talking to what we expect */
ret = max310x_detect(dev);
if (ret)
goto out_clk;
for (i = 0; i < devtype->nr; i++) {
bool started = false;
unsigned int try = 0, val = 0;
/* Reset port */
regmap_write(regmaps[i], MAX310X_MODE2_REG,
MAX310X_MODE2_RST_BIT);
/* Clear port reset */
regmap_write(regmaps[i], MAX310X_MODE2_REG, 0);
/* Wait for port startup */
do {
msleep(MAX310X_PORT_STARTUP_WAIT_DELAY_MS);
regmap_read(regmaps[i], MAX310X_BRGDIVLSB_REG, &val);
if (val == 0x01)
started = true;
} while (!started && (++try < MAX310X_PORT_STARTUP_WAIT_RETRIES));
if (!started) {
ret = dev_err_probe(dev, -EAGAIN, "port reset failed\n");
goto out_uart;
}
regmap_write(regmaps[i], MAX310X_MODE1_REG, devtype->mode1);
}
uartclk = max310x_set_ref_clk(dev, s, freq, xtal);
if (uartclk < 0) {
ret = uartclk;
goto out_uart;
}
dev_dbg(dev, "Reference clock set to %i Hz\n", uartclk);
for (i = 0; i < devtype->nr; i++) {
unsigned int line;
line = find_first_zero_bit(max310x_lines, MAX310X_UART_NRMAX);
if (line == MAX310X_UART_NRMAX) {
ret = -ERANGE;
goto out_uart;
}
/* Initialize port data */
s->p[i].port.line = line;
s->p[i].port.dev = dev;
s->p[i].port.irq = irq;
s->p[i].port.type = PORT_MAX310X;
s->p[i].port.fifosize = MAX310X_FIFO_SIZE;
s->p[i].port.flags = UPF_FIXED_TYPE | UPF_LOW_LATENCY;
s->p[i].port.iotype = UPIO_PORT;
s->p[i].port.iobase = i;
/*
* Use all ones as membase to make sure uart_configure_port() in
* serial_core.c does not abort for SPI/I2C devices where the
* membase address is not applicable.
*/
s->p[i].port.membase = (void __iomem *)~0;
s->p[i].port.uartclk = uartclk;
s->p[i].port.rs485_config = max310x_rs485_config;
s->p[i].port.rs485_supported = max310x_rs485_supported;
s->p[i].port.ops = &max310x_ops;
s->p[i].regmap = regmaps[i];
/* Disable all interrupts */
max310x_port_write(&s->p[i].port, MAX310X_IRQEN_REG, 0);
/* Clear IRQ status register */
max310x_port_read(&s->p[i].port, MAX310X_IRQSTS_REG);
/* Initialize queue for start TX */
INIT_WORK(&s->p[i].tx_work, max310x_tx_proc);
/* Initialize queue for changing LOOPBACK mode */
INIT_WORK(&s->p[i].md_work, max310x_md_proc);
/* Initialize queue for changing RS485 mode */
INIT_WORK(&s->p[i].rs_work, max310x_rs_proc);
/* Register port */
ret = uart_add_one_port(&max310x_uart, &s->p[i].port);
if (ret)
goto out_uart;
set_bit(line, max310x_lines);
/* Go to suspend mode */
max310x_power(&s->p[i].port, 0);
}
#ifdef CONFIG_GPIOLIB
/* Setup GPIO controller */
s->gpio.owner = THIS_MODULE;
s->gpio.parent = dev;
s->gpio.label = devtype->name;
s->gpio.direction_input = max310x_gpio_direction_input;
s->gpio.get = max310x_gpio_get;
s->gpio.direction_output= max310x_gpio_direction_output;
s->gpio.set = max310x_gpio_set;
s->gpio.set_config = max310x_gpio_set_config;
s->gpio.base = -1;
s->gpio.ngpio = devtype->nr * 4;
s->gpio.can_sleep = 1;
ret = devm_gpiochip_add_data(dev, &s->gpio, s);
if (ret)
goto out_uart;
#endif
/* Setup interrupt */
ret = devm_request_threaded_irq(dev, irq, NULL, max310x_ist,
IRQF_ONESHOT | IRQF_SHARED, dev_name(dev), s);
if (!ret)
return 0;
dev_err(dev, "Unable to request IRQ %i\n", irq);
out_uart:
for (i = 0; i < devtype->nr; i++) {
if (test_and_clear_bit(s->p[i].port.line, max310x_lines))
uart_remove_one_port(&max310x_uart, &s->p[i].port);
}
out_clk:
clk_disable_unprepare(s->clk);
return ret;
}
static void max310x_remove(struct device *dev)
{
struct max310x_port *s = dev_get_drvdata(dev);
int i;
for (i = 0; i < s->devtype->nr; i++) {
cancel_work_sync(&s->p[i].tx_work);
cancel_work_sync(&s->p[i].md_work);
cancel_work_sync(&s->p[i].rs_work);
if (test_and_clear_bit(s->p[i].port.line, max310x_lines))
uart_remove_one_port(&max310x_uart, &s->p[i].port);
max310x_power(&s->p[i].port, 0);
}
clk_disable_unprepare(s->clk);
}
static const struct of_device_id __maybe_unused max310x_dt_ids[] = {
{ .compatible = "maxim,max3107", .data = &max3107_devtype, },
{ .compatible = "maxim,max3108", .data = &max3108_devtype, },
{ .compatible = "maxim,max3109", .data = &max3109_devtype, },
{ .compatible = "maxim,max14830", .data = &max14830_devtype },
{ }
};
MODULE_DEVICE_TABLE(of, max310x_dt_ids);
static struct regmap_config regcfg = {
.reg_bits = 8,
.val_bits = 8,
.write_flag_mask = MAX310X_WRITE_BIT,
.cache_type = REGCACHE_MAPLE,
.max_register = MAX310X_REG_1F,
.writeable_reg = max310x_reg_writeable,
.volatile_reg = max310x_reg_volatile,
.precious_reg = max310x_reg_precious,
.writeable_noinc_reg = max310x_reg_noinc,
.readable_noinc_reg = max310x_reg_noinc,
.max_raw_read = MAX310X_FIFO_SIZE,
.max_raw_write = MAX310X_FIFO_SIZE,
};
static const char *max310x_regmap_name(u8 port_id)
{
switch (port_id) {
case 0: return "port0";
case 1: return "port1";
case 2: return "port2";
case 3: return "port3";
default:
WARN_ON(true);
return NULL;
}
}
#ifdef CONFIG_SPI_MASTER
static int max310x_spi_extended_reg_enable(struct device *dev, bool enable)
{
struct max310x_port *s = dev_get_drvdata(dev);
return regmap_write(s->regmap, MAX310X_GLOBALCMD_REG,
enable ? MAX310X_EXTREG_ENBL : MAX310X_EXTREG_DSBL);
}
static const struct max310x_if_cfg __maybe_unused max310x_spi_if_cfg = {
.extended_reg_enable = max310x_spi_extended_reg_enable,
.rev_id_offset = MAX310X_EXTREG_START,
};
static int max310x_spi_probe(struct spi_device *spi)
{
const struct max310x_devtype *devtype;
struct regmap *regmaps[MAX310X_MAX_PORTS];
unsigned int i;
int ret;
/* Setup SPI bus */
spi->bits_per_word = 8;
spi->mode = spi->mode ? : SPI_MODE_0;
spi->max_speed_hz = spi->max_speed_hz ? : 26000000;
ret = spi_setup(spi);
if (ret)
return ret;
devtype = spi_get_device_match_data(spi);
if (!devtype)
return dev_err_probe(&spi->dev, -ENODEV, "Failed to match device\n");
for (i = 0; i < devtype->nr; i++) {
u8 port_mask = i * 0x20;
regcfg.name = max310x_regmap_name(i);
regcfg.read_flag_mask = port_mask;
regcfg.write_flag_mask = port_mask | MAX310X_WRITE_BIT;
regmaps[i] = devm_regmap_init_spi(spi, ®cfg);
}
return max310x_probe(&spi->dev, devtype, &max310x_spi_if_cfg, regmaps, spi->irq);
}
static void max310x_spi_remove(struct spi_device *spi)
{
max310x_remove(&spi->dev);
}
static const struct spi_device_id max310x_id_table[] = {
{ "max3107", (kernel_ulong_t)&max3107_devtype, },
{ "max3108", (kernel_ulong_t)&max3108_devtype, },
{ "max3109", (kernel_ulong_t)&max3109_devtype, },
{ "max14830", (kernel_ulong_t)&max14830_devtype, },
{ }
};
MODULE_DEVICE_TABLE(spi, max310x_id_table);
static struct spi_driver max310x_spi_driver = {
.driver = {
.name = MAX310X_NAME,
.of_match_table = max310x_dt_ids,
.pm = &max310x_pm_ops,
},
.probe = max310x_spi_probe,
.remove = max310x_spi_remove,
.id_table = max310x_id_table,
};
#endif
#ifdef CONFIG_I2C
static int max310x_i2c_extended_reg_enable(struct device *dev, bool enable)
{
return 0;
}
static struct regmap_config regcfg_i2c = {
.reg_bits = 8,
.val_bits = 8,
.cache_type = REGCACHE_MAPLE,
.writeable_reg = max310x_reg_writeable,
.volatile_reg = max310x_reg_volatile,
.precious_reg = max310x_reg_precious,
.max_register = MAX310X_REVID_EXTREG,
.writeable_noinc_reg = max310x_reg_noinc,
.readable_noinc_reg = max310x_reg_noinc,
.max_raw_read = MAX310X_FIFO_SIZE,
.max_raw_write = MAX310X_FIFO_SIZE,
};
static const struct max310x_if_cfg max310x_i2c_if_cfg = {
.extended_reg_enable = max310x_i2c_extended_reg_enable,
.rev_id_offset = 0, /* No offset in I2C mode. */
};
static unsigned short max310x_i2c_slave_addr(unsigned short addr,
unsigned int nr)
{
/*
* For MAX14830 and MAX3109, the slave address depends on what the
* A0 and A1 pins are tied to.
* See Table I2C Address Map of the datasheet.
* Based on that table, the following formulas were determined:
* UART1 - UART0 = 0x10
* UART2 - UART1 = 0x20 + 0x10
* UART3 - UART2 = 0x10
*/
addr -= nr * 0x10;
if (nr >= 2)
addr -= 0x20;
return addr;
}
static int max310x_i2c_probe(struct i2c_client *client)
{
const struct max310x_devtype *devtype;
struct i2c_client *port_client;
struct regmap *regmaps[MAX310X_MAX_PORTS];
unsigned int i;
u8 port_addr;
devtype = i2c_get_match_data(client);
if (!devtype)
return dev_err_probe(&client->dev, -ENODEV, "Failed to match device\n");
if (client->addr < devtype->slave_addr.min ||
client->addr > devtype->slave_addr.max)
return dev_err_probe(&client->dev, -EINVAL,
"Slave addr 0x%x outside of range [0x%x, 0x%x]\n",
client->addr, devtype->slave_addr.min,
devtype->slave_addr.max);
regcfg_i2c.name = max310x_regmap_name(0);
regmaps[0] = devm_regmap_init_i2c(client, ®cfg_i2c);
for (i = 1; i < devtype->nr; i++) {
port_addr = max310x_i2c_slave_addr(client->addr, i);
port_client = devm_i2c_new_dummy_device(&client->dev,
client->adapter,
port_addr);
regcfg_i2c.name = max310x_regmap_name(i);
regmaps[i] = devm_regmap_init_i2c(port_client, ®cfg_i2c);
}
return max310x_probe(&client->dev, devtype, &max310x_i2c_if_cfg,
regmaps, client->irq);
}
static void max310x_i2c_remove(struct i2c_client *client)
{
max310x_remove(&client->dev);
}
static const struct i2c_device_id max310x_i2c_id_table[] = {
{ "max3107", (kernel_ulong_t)&max3107_devtype, },
{ "max3108", (kernel_ulong_t)&max3108_devtype, },
{ "max3109", (kernel_ulong_t)&max3109_devtype, },
{ "max14830", (kernel_ulong_t)&max14830_devtype, },
{ }
};
MODULE_DEVICE_TABLE(i2c, max310x_i2c_id_table);
static struct i2c_driver max310x_i2c_driver = {
.driver = {
.name = MAX310X_NAME,
.of_match_table = max310x_dt_ids,
.pm = &max310x_pm_ops,
},
.probe = max310x_i2c_probe,
.remove = max310x_i2c_remove,
.id_table = max310x_i2c_id_table,
};
#endif
static int __init max310x_uart_init(void)
{
int ret;
bitmap_zero(max310x_lines, MAX310X_UART_NRMAX);
ret = uart_register_driver(&max310x_uart);
if (ret)
return ret;
#ifdef CONFIG_SPI_MASTER
ret = spi_register_driver(&max310x_spi_driver);
if (ret)
goto err_spi_register;
#endif
#ifdef CONFIG_I2C
ret = i2c_add_driver(&max310x_i2c_driver);
if (ret)
goto err_i2c_register;
#endif
return 0;
#ifdef CONFIG_I2C
err_i2c_register:
spi_unregister_driver(&max310x_spi_driver);
#endif
err_spi_register:
uart_unregister_driver(&max310x_uart);
return ret;
}
module_init(max310x_uart_init);
static void __exit max310x_uart_exit(void)
{
#ifdef CONFIG_I2C
i2c_del_driver(&max310x_i2c_driver);
#endif
#ifdef CONFIG_SPI_MASTER
spi_unregister_driver(&max310x_spi_driver);
#endif
uart_unregister_driver(&max310x_uart);
}
module_exit(max310x_uart_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Alexander Shiyan <[email protected]>");
MODULE_DESCRIPTION("MAX310X serial driver");
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