[PATCH v4 1/2] serial: sc16is7xx

From: jon
Date: Thu Apr 03 2014 - 00:50:26 EST

From: Jon Ringle <jringle@xxxxxxxxxxxxx>

The SC16IS7xx is a slave I2C-bus/SPI interface to a single-channel
high performance UART. The SC16IS7xxâs internal register set is
backward-compatible with the widely used and widely popular 16C450.

The SC16IS7xx also provides additional advanced features such as
auto hardware and software flow control, automatic RS-485 support, and
software reset.

Signed-off-by: Jon Ringle <jringle@xxxxxxxxxxxxx>
---
drivers/tty/serial/Kconfig | 10 +
drivers/tty/serial/Makefile | 1 +
drivers/tty/serial/sc16is7xx.c | 1305 ++++++++++++++++++++++++++++++++++++++
include/uapi/linux/serial_core.h | 3 +
4 files changed, 1319 insertions(+)
create mode 100644 drivers/tty/serial/sc16is7xx.c

diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index febd45c..6e8fe23 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -1179,6 +1179,16 @@ config SERIAL_SCCNXP_CONSOLE
help
Support for console on SCCNXP serial ports.

+config SERIAL_SC16IS7XX
+ tristate "SC16IS7xx serial support"
+ select SERIAL_CORE
+ select REGMAP_I2C if I2C
+ default n
+ help
+ This selects support for SC16IS7xx serial ports.
+ Supported ICs are SC16IS740, SC16IS741, SC16IS750, SC16IS752,
+ SC16IS760 and SC16IS762.
+
config SERIAL_BFIN_SPORT
tristate "Blackfin SPORT emulate UART"
depends on BLACKFIN
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index 3068c77..c3bac45 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -49,6 +49,7 @@ obj-$(CONFIG_SERIAL_SB1250_DUART) += sb1250-duart.o
obj-$(CONFIG_ETRAX_SERIAL) += crisv10.o
obj-$(CONFIG_SERIAL_SC26XX) += sc26xx.o
obj-$(CONFIG_SERIAL_SCCNXP) += sccnxp.o
+obj-$(CONFIG_SERIAL_SC16IS7XX) += sc16is7xx.o
obj-$(CONFIG_SERIAL_JSM) += jsm/
obj-$(CONFIG_SERIAL_TXX9) += serial_txx9.o
obj-$(CONFIG_SERIAL_VR41XX) += vr41xx_siu.o
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
new file mode 100644
index 0000000..cf10342
--- /dev/null
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -0,0 +1,1305 @@
+/*
+ * SC16IS7xx tty serial driver - Copyright (C) 2014 GridPoint
+ * Author: Jon Ringle <jringle@xxxxxxxxxxxxx>
+ *
+ * Based on max310x.c, by Alexander Shiyan <shc_work@xxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/gpio.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+#include <linux/spi/spi.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+
+#define SC16IS7XX_NAME "sc16is7xx"
+
+/* SC16IS7XX register definitions */
+#define SC16IS7XX_RHR_REG (0x00) /* RX FIFO */
+#define SC16IS7XX_THR_REG (0x00) /* TX FIFO */
+#define SC16IS7XX_IER_REG (0x01) /* Interrupt enable */
+#define SC16IS7XX_IIR_REG (0x02) /* Interrupt Identification */
+#define SC16IS7XX_FCR_REG (0x02) /* FIFO control */
+#define SC16IS7XX_LCR_REG (0x03) /* Line Control */
+#define SC16IS7XX_MCR_REG (0x04) /* Modem Control */
+#define SC16IS7XX_LSR_REG (0x05) /* Line Status */
+#define SC16IS7XX_MSR_REG (0x06) /* Modem Status */
+#define SC16IS7XX_SPR_REG (0x07) /* Scratch Pad */
+#define SC16IS7XX_TXLVL_REG (0x08) /* TX FIFO level */
+#define SC16IS7XX_RXLVL_REG (0x09) /* RX FIFO level */
+#define SC16IS7XX_IODIR_REG (0x0a) /* I/O Direction
+ * - only on 75x/76x
+ */
+#define SC16IS7XX_IOSTATE_REG (0x0b) /* I/O State
+ * - only on 75x/76x
+ */
+#define SC16IS7XX_IOINTENA_REG (0x0c) /* I/O Interrupt Enable
+ * - only on 75x/76x
+ */
+#define SC16IS7XX_IOCONTROL_REG (0x0e) /* I/O Control
+ * - only on 75x/76x
+ */
+#define SC16IS7XX_EFCR_REG (0x0f) /* Extra Features Control */
+
+/* TCR/TLR Register set: Only if ((MCR[2] == 1) && (EFR[4] == 1)) */
+#define SC16IS7XX_TCR_REG (0x06) /* Transmit control */
+#define SC16IS7XX_TLR_REG (0x07) /* Trigger level */
+
+/* Special Register set: Only if ((LCR[7] == 1) && (LCR != 0xBF)) */
+#define SC16IS7XX_DLL_REG (0x00) /* Divisor Latch Low */
+#define SC16IS7XX_DLH_REG (0x01) /* Divisor Latch High */
+
+/* Enhanced Register set: Only if (LCR == 0xBF) */
+#define SC16IS7XX_EFR_REG (0x02) /* Enhanced Features */
+#define SC16IS7XX_XON1_REG (0x04) /* Xon1 word */
+#define SC16IS7XX_XON2_REG (0x05) /* Xon2 word */
+#define SC16IS7XX_XOFF1_REG (0x06) /* Xoff1 word */
+#define SC16IS7XX_XOFF2_REG (0x07) /* Xoff2 word */
+
+/* IER register bits */
+#define SC16IS7XX_IER_RDI_BIT (1 << 0) /* Enable RX data interrupt */
+#define SC16IS7XX_IER_THRI_BIT (1 << 1) /* Enable TX holding register
+ * interrupt */
+#define SC16IS7XX_IER_RLSI_BIT (1 << 2) /* Enable RX line status
+ * interrupt */
+#define SC16IS7XX_IER_MSI_BIT (1 << 3) /* Enable Modem status
+ * interrupt */
+
+/* IER register bits - write only if (EFR[4] == 1) */
+#define SC16IS7XX_IER_SLEEP_BIT (1 << 4) /* Enable Sleep mode */
+#define SC16IS7XX_IER_XOFFI_BIT (1 << 5) /* Enable Xoff interrupt */
+#define SC16IS7XX_IER_RTSI_BIT (1 << 6) /* Enable nRTS interrupt */
+#define SC16IS7XX_IER_CTSI_BIT (1 << 7) /* Enable nCTS interrupt */
+
+/* FCR register bits */
+#define SC16IS7XX_FCR_FIFO_BIT (1 << 0) /* Enable FIFO */
+#define SC16IS7XX_FCR_RXRESET_BIT (1 << 1) /* Reset RX FIFO */
+#define SC16IS7XX_FCR_TXRESET_BIT (1 << 2) /* Reset TX FIFO */
+#define SC16IS7XX_FCR_RXLVLL_BIT (1 << 6) /* RX Trigger level LSB */
+#define SC16IS7XX_FCR_RXLVLH_BIT (1 << 7) /* RX Trigger level MSB */
+
+/* FCR register bits - write only if (EFR[4] == 1) */
+#define SC16IS7XX_FCR_TXLVLL_BIT (1 << 4) /* TX Trigger level LSB */
+#define SC16IS7XX_FCR_TXLVLH_BIT (1 << 5) /* TX Trigger level MSB */
+
+/* IIR register bits */
+#define SC16IS7XX_IIR_NO_INT_BIT (1 << 0) /* No interrupts pending */
+#define SC16IS7XX_IIR_ID_MASK 0x3e /* Mask for the interrupt ID */
+#define SC16IS7XX_IIR_THRI_SRC 0x02 /* TX holding register empty */
+#define SC16IS7XX_IIR_RDI_SRC 0x04 /* RX data interrupt */
+#define SC16IS7XX_IIR_RLSE_SRC 0x06 /* RX line status error */
+#define SC16IS7XX_IIR_RTOI_SRC 0x0c /* RX time-out interrupt */
+#define SC16IS7XX_IIR_MSI_SRC 0x00 /* Modem status interrupt
+ * - only on 75x/76x
+ */
+#define SC16IS7XX_IIR_INPIN_SRC 0x30 /* Input pin change of state
+ * - only on 75x/76x
+ */
+#define SC16IS7XX_IIR_XOFFI_SRC 0x10 /* Received Xoff */
+#define SC16IS7XX_IIR_CTSRTS_SRC 0x20 /* nCTS,nRTS change of state
+ * from active (LOW)
+ * to inactive (HIGH)
+ */
+/* LCR register bits */
+#define SC16IS7XX_LCR_LENGTH0_BIT (1 << 0) /* Word length bit 0 */
+#define SC16IS7XX_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 SC16IS7XX_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 SC16IS7XX_LCR_PARITY_BIT (1 << 3) /* Parity bit enable */
+#define SC16IS7XX_LCR_EVENPARITY_BIT (1 << 4) /* Even parity bit enable */
+#define SC16IS7XX_LCR_FORCEPARITY_BIT (1 << 5) /* 9-bit multidrop parity */
+#define SC16IS7XX_LCR_TXBREAK_BIT (1 << 6) /* TX break enable */
+#define SC16IS7XX_LCR_DLAB_BIT (1 << 7) /* Divisor Latch enable */
+#define SC16IS7XX_LCR_WORD_LEN_5 (0x00)
+#define SC16IS7XX_LCR_WORD_LEN_6 (0x01)
+#define SC16IS7XX_LCR_WORD_LEN_7 (0x02)
+#define SC16IS7XX_LCR_WORD_LEN_8 (0x03)
+#define SC16IS7XX_LCR_CONF_MODE_A SC16IS7XX_LCR_DLAB_BIT /* Special
+ * reg set */
+#define SC16IS7XX_LCR_CONF_MODE_B 0xBF /* Enhanced
+ * reg set */
+
+/* MCR register bits */
+#define SC16IS7XX_MCR_DTR_BIT (1 << 0) /* DTR complement
+ * - only on 75x/76x
+ */
+#define SC16IS7XX_MCR_RTS_BIT (1 << 1) /* RTS complement */
+#define SC16IS7XX_MCR_TCRTLR_BIT (1 << 2) /* TCR/TLR register enable */
+#define SC16IS7XX_MCR_LOOP_BIT (1 << 4) /* Enable loopback test mode */
+#define SC16IS7XX_MCR_XONANY_BIT (1 << 5) /* Enable Xon Any
+ * - write enabled
+ * if (EFR[4] == 1)
+ */
+#define SC16IS7XX_MCR_IRDA_BIT (1 << 6) /* Enable IrDA mode
+ * - write enabled
+ * if (EFR[4] == 1)
+ */
+#define SC16IS7XX_MCR_CLKSEL_BIT (1 << 7) /* Divide clock by 4
+ * - write enabled
+ * if (EFR[4] == 1)
+ */
+
+/* LSR register bits */
+#define SC16IS7XX_LSR_DR_BIT (1 << 0) /* Receiver data ready */
+#define SC16IS7XX_LSR_OE_BIT (1 << 1) /* Overrun Error */
+#define SC16IS7XX_LSR_PE_BIT (1 << 2) /* Parity Error */
+#define SC16IS7XX_LSR_FE_BIT (1 << 3) /* Frame Error */
+#define SC16IS7XX_LSR_BI_BIT (1 << 4) /* Break Interrupt */
+#define SC16IS7XX_LSR_BRK_ERROR_MASK 0x1E /* BI, FE, PE, OE bits */
+#define SC16IS7XX_LSR_THRE_BIT (1 << 5) /* TX holding register empty */
+#define SC16IS7XX_LSR_TEMT_BIT (1 << 6) /* Transmitter empty */
+#define SC16IS7XX_LSR_FIFOE_BIT (1 << 7) /* Fifo Error */
+
+/* MSR register bits */
+#define SC16IS7XX_MSR_DCTS_BIT (1 << 0) /* Delta CTS Clear To Send */
+#define SC16IS7XX_MSR_DDSR_BIT (1 << 1) /* Delta DSR Data Set Ready
+ * or (IO4)
+ * - only on 75x/76x
+ */
+#define SC16IS7XX_MSR_DRI_BIT (1 << 2) /* Delta RI Ring Indicator
+ * or (IO7)
+ * - only on 75x/76x
+ */
+#define SC16IS7XX_MSR_DCD_BIT (1 << 3) /* Delta CD Carrier Detect
+ * or (IO6)
+ * - only on 75x/76x
+ */
+#define SC16IS7XX_MSR_CTS_BIT (1 << 0) /* CTS */
+#define SC16IS7XX_MSR_DSR_BIT (1 << 1) /* DSR (IO4)
+ * - only on 75x/76x
+ */
+#define SC16IS7XX_MSR_RI_BIT (1 << 2) /* RI (IO7)
+ * - only on 75x/76x
+ */
+#define SC16IS7XX_MSR_CD_BIT (1 << 3) /* CD (IO6)
+ * - only on 75x/76x
+ */
+#define SC16IS7XX_MSR_DELTA_MASK 0x0F /* Any of the delta bits! */
+
+/*
+ * TCR register bits
+ * TCR trigger levels are available from 0 to 60 characters with a granularity
+ * of four.
+ * The programmer must program the TCR such that TCR[3:0] > TCR[7:4]. There is
+ * no built-in hardware check to make sure this condition is met. Also, the TCR
+ * must be programmed with this condition before auto RTS or software flow
+ * control is enabled to avoid spurious operation of the device.
+ */
+#define SC16IS7XX_TCR_RX_HALT(words) (((words / 4) & 0x0f) << 0)
+#define SC16IS7XX_TCR_RX_RESUME(words) (((words / 4) & 0x0f) << 4)
+
+/*
+ * TLR register bits
+ * If TLR[3:0] or TLR[7:4] are logical 0, the selectable trigger levels via the
+ * FIFO Control Register (FCR) are used for the transmit and receive FIFO
+ * trigger levels. Trigger levels from 4 characters to 60 characters are
+ * available with a granularity of four.
+ *
+ * When the trigger level setting in TLR is zero, the SC16IS740/750/760 uses the
+ * trigger level setting defined in FCR. If TLR has non-zero trigger level value
+ * the trigger level defined in FCR is discarded. This applies to both transmit
+ * FIFO and receive FIFO trigger level setting.
+ *
+ * When TLR is used for RX trigger level control, FCR[7:6] should be left at the
+ * default state, that is, â00â.
+ */
+#define SC16IS7XX_TLR_TX_TRIGGER(words) (((words / 4) & 0x0f) << 0)
+#define SC16IS7XX_TLR_RX_TRIGGER(words) (((words / 4) & 0x0f) << 4)
+
+/* IOControl register bits (Only 750/760) */
+#define SC16IS7XX_IOCONTROL_LATCH_BIT (1 << 0) /* Enable input latching */
+#define SC16IS7XX_IOCONTROL_GPIO_BIT (1 << 1) /* Enable GPIO[7:4] */
+#define SC16IS7XX_IOCONTROL_SRESET_BIT (1 << 3) /* Software Reset */
+
+/* EFCR register bits */
+#define SC16IS7XX_EFCR_9BIT_MODE_BIT (1 << 0) /* Enable 9-bit or Multidrop
+ * mode (RS485) */
+#define SC16IS7XX_EFCR_RXDISABLE_BIT (1 << 1) /* Disable receiver */
+#define SC16IS7XX_EFCR_TXDISABLE_BIT (1 << 2) /* Disable transmitter */
+#define SC16IS7XX_EFCR_AUTO_RS485_BIT (1 << 4) /* Auto RS485 RTS direction */
+#define SC16IS7XX_EFCR_RTS_INVERT_BIT (1 << 5) /* RTS output inversion */
+#define SC16IS7XX_EFCR_IRDA_MODE_BIT (1 << 7) /* IrDA mode
+ * 0 = rate upto 115.2 kbit/s
+ * - Only 750/760
+ * 1 = rate upto 1.152 Mbit/s
+ * - Only 760
+ */
+
+/* EFR register bits */
+#define SC16IS7XX_EFR_AUTORTS_BIT (1 << 6) /* Auto RTS flow ctrl enable */
+#define SC16IS7XX_EFR_AUTOCTS_BIT (1 << 7) /* Auto CTS flow ctrl enable */
+#define SC16IS7XX_EFR_XOFF2_DETECT_BIT (1 << 5) /* Enable Xoff2 detection */
+#define SC16IS7XX_EFR_ENABLE_BIT (1 << 4) /* Enable enhanced functions
+ * and writing to IER[7:4],
+ * FCR[5:4], MCR[7:5]
+ */
+#define SC16IS7XX_EFR_SWFLOW3_BIT (1 << 3) /* SWFLOW bit 3 */
+#define SC16IS7XX_EFR_SWFLOW2_BIT (1 << 2) /* SWFLOW bit 2
+ *
+ * SWFLOW bits 3 & 2 table:
+ * 00 -> no transmitter flow
+ * control
+ * 01 -> transmitter generates
+ * XON2 and XOFF2
+ * 10 -> transmitter generates
+ * XON1 and XOFF1
+ * 11 -> transmitter generates
+ * XON1, XON2, XOFF1 and
+ * XOFF2
+ */
+#define SC16IS7XX_EFR_SWFLOW1_BIT (1 << 1) /* SWFLOW bit 2 */
+#define SC16IS7XX_EFR_SWFLOW0_BIT (1 << 0) /* SWFLOW bit 3
+ *
+ * SWFLOW bits 3 & 2 table:
+ * 00 -> no received flow
+ * control
+ * 01 -> receiver compares
+ * XON2 and XOFF2
+ * 10 -> receiver compares
+ * XON1 and XOFF1
+ * 11 -> receiver compares
+ * XON1, XON2, XOFF1 and
+ * XOFF2
+ */
+
+/* Misc definitions */
+#define SC16IS7XX_FIFO_SIZE (64)
+#define SC16IS7XX_REG_SHIFT 2
+
+struct sc16is7xx_devtype {
+ char name[10];
+ int nr_gpio;
+ int nr_uart;
+};
+
+struct sc16is7xx_one {
+ struct uart_port port;
+ struct work_struct tx_work;
+ struct work_struct md_work;
+
+ struct serial_rs485 rs485;
+};
+
+struct sc16is7xx_port {
+ struct uart_driver uart;
+ struct sc16is7xx_devtype *devtype;
+ struct regmap *regmap;
+ struct mutex mutex;
+ struct clk *clk;
+#ifdef CONFIG_GPIOLIB
+ struct gpio_chip gpio;
+#endif
+ struct sc16is7xx_one p[0];
+};
+
+#define to_sc16is7xx_one(p,e) ((container_of((p), struct sc16is7xx_one, e)))
+
+static u8 sc16is7xx_port_read(struct uart_port *port, u8 reg)
+{
+ struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+ unsigned int val = 0;
+
+ regmap_read(s->regmap,
+ (reg << SC16IS7XX_REG_SHIFT) | port->line, &val);
+
+ return val;
+}
+
+static void sc16is7xx_port_write(struct uart_port *port, u8 reg, u8 val)
+{
+ struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+
+ regmap_write(s->regmap,
+ (reg << SC16IS7XX_REG_SHIFT) | port->line, val);
+}
+
+static void sc16is7xx_port_update(struct uart_port *port, u8 reg,
+ u8 mask, u8 val)
+{
+ struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+
+ regmap_update_bits(s->regmap,
+ (reg << SC16IS7XX_REG_SHIFT) | port->line,
+ mask, val);
+}
+
+
+static void sc16is7xx_power(struct uart_port *port, int on)
+{
+ sc16is7xx_port_update(port, SC16IS7XX_IER_REG,
+ SC16IS7XX_IER_SLEEP_BIT,
+ on ? 0 : SC16IS7XX_IER_SLEEP_BIT);
+}
+
+static const struct sc16is7xx_devtype sc16is74x_devtype = {
+ .name = "SC16IS74X",
+ .nr_gpio = 0,
+ .nr_uart = 1,
+};
+
+static const struct sc16is7xx_devtype sc16is750_devtype = {
+ .name = "SC16IS750",
+ .nr_gpio = 8,
+ .nr_uart = 1,
+};
+
+static const struct sc16is7xx_devtype sc16is752_devtype = {
+ .name = "SC16IS752",
+ .nr_gpio = 8,
+ .nr_uart = 2,
+};
+
+static const struct sc16is7xx_devtype sc16is760_devtype = {
+ .name = "SC16IS760",
+ .nr_gpio = 8,
+ .nr_uart = 1,
+};
+
+static const struct sc16is7xx_devtype sc16is762_devtype = {
+ .name = "SC16IS762",
+ .nr_gpio = 8,
+ .nr_uart = 2,
+};
+
+static bool sc16is7xx_regmap_writeable(struct device *dev, unsigned int reg)
+{
+ switch (reg >> SC16IS7XX_REG_SHIFT) {
+ case SC16IS7XX_THR_REG:
+ case SC16IS7XX_IER_REG:
+ case SC16IS7XX_FCR_REG:
+ case SC16IS7XX_LCR_REG:
+ case SC16IS7XX_MCR_REG:
+ case SC16IS7XX_SPR_REG:
+ case SC16IS7XX_IODIR_REG:
+ case SC16IS7XX_IOSTATE_REG:
+ case SC16IS7XX_IOINTENA_REG:
+ case SC16IS7XX_IOCONTROL_REG:
+ case SC16IS7XX_EFCR_REG:
+ return true;
+ default:
+ break;
+ }
+
+ return false;
+}
+
+static bool sc16is7xx_regmap_volatile(struct device *dev, unsigned int reg)
+{
+ switch (reg >> SC16IS7XX_REG_SHIFT) {
+ case SC16IS7XX_RHR_REG:
+ case SC16IS7XX_IIR_REG:
+ case SC16IS7XX_LSR_REG:
+ case SC16IS7XX_MSR_REG:
+ case SC16IS7XX_TXLVL_REG:
+ case SC16IS7XX_RXLVL_REG:
+ case SC16IS7XX_IOSTATE_REG:
+ return true;
+ default:
+ break;
+ }
+
+ return false;
+}
+
+static bool sc16is7xx_regmap_precious(struct device *dev, unsigned int reg)
+{
+ switch (reg >> SC16IS7XX_REG_SHIFT) {
+ case SC16IS7XX_RHR_REG:
+ return true;
+ default:
+ break;
+ }
+
+ return false;
+}
+
+static int sc16is7xx_set_baud(struct uart_port *port, int baud)
+{
+ struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+ u8 lcr;
+ u8 prescaler = 0;
+ unsigned long clk = port->uartclk, div = clk / 16 / baud;
+
+ if (div > 0xffff) {
+ prescaler = SC16IS7XX_MCR_CLKSEL_BIT;
+ div /= 4;
+ }
+
+ lcr = sc16is7xx_port_read(port, SC16IS7XX_LCR_REG);
+
+ /* Open the LCR divisors for configuration */
+ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
+ SC16IS7XX_LCR_CONF_MODE_B);
+
+ /* Enable enhanced features */
+ regcache_cache_bypass(s->regmap, true);
+ sc16is7xx_port_write(port, SC16IS7XX_EFR_REG,
+ SC16IS7XX_EFR_ENABLE_BIT);
+ regcache_cache_bypass(s->regmap, false);
+
+ /* Put LCR back to the normal mode */
+ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
+
+ sc16is7xx_port_update(port, SC16IS7XX_MCR_REG,
+ SC16IS7XX_MCR_CLKSEL_BIT,
+ prescaler);
+
+ /* Open the LCR divisors for configuration */
+ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
+ SC16IS7XX_LCR_CONF_MODE_A);
+
+ /* Write the new divisor */
+ regcache_cache_bypass(s->regmap, true);
+ sc16is7xx_port_write(port, SC16IS7XX_DLH_REG, div / 256);
+ sc16is7xx_port_write(port, SC16IS7XX_DLL_REG, div % 256);
+ regcache_cache_bypass(s->regmap, false);
+
+ /* Put LCR back to the normal mode */
+ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
+
+ return DIV_ROUND_CLOSEST(clk / 16, div);
+}
+
+static void sc16is7xx_handle_rx(struct uart_port *port, unsigned int rxlen,
+ unsigned int iir)
+{
+ struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+ unsigned int lsr = 0, ch, flag, bytes_read, i;
+ u8 buf[port->fifosize];
+ bool read_lsr = (iir == SC16IS7XX_IIR_RLSE_SRC) ? true : false;
+
+ if (unlikely(rxlen >= port->fifosize)) {
+ dev_warn_ratelimited(port->dev,
+ "Port %i: Possible RX FIFO overrun: %d\n",
+ port->line, rxlen);
+ port->icount.buf_overrun++;
+ /* Ensure sanity of RX level */
+ rxlen = port->fifosize;
+ }
+
+ while (rxlen) {
+ /* Only read lsr if there are possible errors in FIFO */
+ if (read_lsr) {
+ lsr = sc16is7xx_port_read(port, SC16IS7XX_LSR_REG);
+ if (!(lsr & SC16IS7XX_LSR_FIFOE_BIT))
+ read_lsr = false; /* No errors left in FIFO */
+ } else
+ lsr = 0;
+
+ if (read_lsr) {
+ buf[0] = sc16is7xx_port_read(port, SC16IS7XX_RHR_REG);
+ bytes_read = 1;
+ } else {
+ regcache_cache_bypass(s->regmap, true);
+ regmap_raw_read(s->regmap, SC16IS7XX_RHR_REG,
+ buf, rxlen);
+ regcache_cache_bypass(s->regmap, false);
+ bytes_read = rxlen;
+ }
+
+ lsr &= SC16IS7XX_LSR_BRK_ERROR_MASK;
+
+ port->icount.rx++;
+ flag = TTY_NORMAL;
+
+ if (unlikely(lsr)) {
+ if (lsr & SC16IS7XX_LSR_BI_BIT) {
+ port->icount.brk++;
+ if (uart_handle_break(port))
+ continue;
+ } else if (lsr & SC16IS7XX_LSR_PE_BIT)
+ port->icount.parity++;
+ else if (lsr & SC16IS7XX_LSR_FE_BIT)
+ port->icount.frame++;
+ else if (lsr & SC16IS7XX_LSR_OE_BIT)
+ port->icount.overrun++;
+
+ lsr &= port->read_status_mask;
+ if (lsr & SC16IS7XX_LSR_BI_BIT)
+ flag = TTY_BREAK;
+ else if (lsr & SC16IS7XX_LSR_PE_BIT)
+ flag = TTY_PARITY;
+ else if (lsr & SC16IS7XX_LSR_FE_BIT)
+ flag = TTY_FRAME;
+ else if (lsr & SC16IS7XX_LSR_OE_BIT)
+ flag = TTY_OVERRUN;
+ }
+
+ for (i = 0; i < bytes_read; ++i) {
+ ch = buf[i];
+ if (uart_handle_sysrq_char(port, ch))
+ continue;
+
+ if (lsr & port->ignore_status_mask)
+ continue;
+
+ uart_insert_char(port, lsr, SC16IS7XX_LSR_OE_BIT, ch,
+ flag);
+ }
+ rxlen -= bytes_read;
+ }
+
+ tty_flip_buffer_push(&port->state->port);
+}
+
+static void sc16is7xx_handle_tx(struct uart_port *port)
+{
+ struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+ struct circ_buf *xmit = &port->state->xmit;
+ unsigned int txlen, to_send, i;
+ u8 buf[port->fifosize];
+
+ if (unlikely(port->x_char)) {
+ sc16is7xx_port_write(port, SC16IS7XX_THR_REG, port->x_char);
+ port->icount.tx++;
+ port->x_char = 0;
+ return;
+ }
+
+ if (uart_circ_empty(xmit) || uart_tx_stopped(port))
+ return;
+
+ /* Get length of data pending in circular buffer */
+ to_send = uart_circ_chars_pending(xmit);
+ if (likely(to_send)) {
+ /* Limit to size of TX FIFO */
+ txlen = sc16is7xx_port_read(port, SC16IS7XX_TXLVL_REG);
+ to_send = (to_send > txlen) ? txlen : to_send;
+
+ /* Add data to send */
+ port->icount.tx += to_send;
+
+ /* Convert to linear buffer */
+ for (i = 0; i < to_send; ++i) {
+ buf[i] = xmit->buf[xmit->tail];
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ }
+ regcache_cache_bypass(s->regmap, true);
+ regmap_raw_write(s->regmap, SC16IS7XX_THR_REG, buf, to_send);
+ regcache_cache_bypass(s->regmap, false);
+ }
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(port);
+}
+
+static void sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno)
+{
+ struct uart_port *port = &s->p[portno].port;
+
+ do {
+ unsigned int iir, msr, rxlen;
+
+ iir = sc16is7xx_port_read(port, SC16IS7XX_IIR_REG);
+ if (iir & SC16IS7XX_IIR_NO_INT_BIT)
+ break;
+
+ iir &= SC16IS7XX_IIR_ID_MASK;
+
+ switch (iir) {
+ case SC16IS7XX_IIR_RDI_SRC:
+ case SC16IS7XX_IIR_RLSE_SRC:
+ case SC16IS7XX_IIR_RTOI_SRC:
+ case SC16IS7XX_IIR_XOFFI_SRC:
+ rxlen = sc16is7xx_port_read(port, SC16IS7XX_RXLVL_REG);
+ if (rxlen)
+ sc16is7xx_handle_rx(port, rxlen, iir);
+ break;
+
+ case SC16IS7XX_IIR_CTSRTS_SRC:
+ msr = sc16is7xx_port_read(port, SC16IS7XX_MSR_REG);
+ uart_handle_cts_change(port,
+ !!(msr & SC16IS7XX_MSR_CTS_BIT));
+ break;
+ case SC16IS7XX_IIR_THRI_SRC:
+ mutex_lock(&s->mutex);
+ sc16is7xx_handle_tx(port);
+ mutex_unlock(&s->mutex);
+ break;
+ default:
+ dev_err_ratelimited(port->dev,
+ "Port %i: Unexpected interrupt: %x",
+ port->line, iir);
+ break;
+ }
+ } while (1);
+}
+
+static irqreturn_t sc16is7xx_ist(int irq, void *dev_id)
+{
+ struct sc16is7xx_port *s = (struct sc16is7xx_port *)dev_id;
+ int i;
+
+ for (i = 0; i < s->uart.nr; ++i)
+ sc16is7xx_port_irq(s, i);
+
+ return IRQ_HANDLED;
+}
+
+static void sc16is7xx_wq_proc(struct work_struct *ws)
+{
+ struct sc16is7xx_one *one = to_sc16is7xx_one(ws, tx_work);
+ struct sc16is7xx_port *s = dev_get_drvdata(one->port.dev);
+
+ mutex_lock(&s->mutex);
+ sc16is7xx_handle_tx(&one->port);
+ mutex_unlock(&s->mutex);
+}
+
+static void sc16is7xx_stop_tx(struct uart_port* port)
+{
+ struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
+ struct circ_buf *xmit = &one->port.state->xmit;
+
+ /* handle rs485 */
+ if (one->rs485.flags & SER_RS485_ENABLED) {
+ /* do nothing if current tx not yet completed */
+ int lsr = sc16is7xx_port_read(port, SC16IS7XX_LSR_REG);
+ if (!(lsr & SC16IS7XX_LSR_TEMT_BIT))
+ return;
+
+ if (uart_circ_empty(xmit) &&
+ (one->rs485.delay_rts_after_send > 0))
+ mdelay(one->rs485.delay_rts_after_send);
+ }
+
+ sc16is7xx_port_update(port, SC16IS7XX_IER_REG,
+ SC16IS7XX_IER_THRI_BIT,
+ 0);
+}
+
+static void sc16is7xx_stop_rx(struct uart_port* port)
+{
+ struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
+
+ one->port.read_status_mask &= ~SC16IS7XX_LSR_DR_BIT;
+ sc16is7xx_port_update(port, SC16IS7XX_IER_REG,
+ SC16IS7XX_LSR_DR_BIT,
+ 0);
+}
+
+static void sc16is7xx_start_tx(struct uart_port *port)
+{
+ struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
+
+ /* handle rs485 */
+ if ((one->rs485.flags & SER_RS485_ENABLED) &&
+ (one->rs485.delay_rts_before_send > 0)) {
+ mdelay(one->rs485.delay_rts_before_send);
+ }
+
+ if (!work_pending(&one->tx_work))
+ schedule_work(&one->tx_work);
+}
+
+static unsigned int sc16is7xx_tx_empty(struct uart_port *port)
+{
+ unsigned int lvl, lsr;
+
+ lvl = sc16is7xx_port_read(port, SC16IS7XX_TXLVL_REG);
+ lsr = sc16is7xx_port_read(port, SC16IS7XX_LSR_REG);
+
+ return ((lsr & SC16IS7XX_LSR_THRE_BIT) && !lvl) ? TIOCSER_TEMT : 0;
+}
+
+static unsigned int sc16is7xx_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 sc16is7xx_md_proc(struct work_struct *ws)
+{
+ struct sc16is7xx_one *one = to_sc16is7xx_one(ws, md_work);
+
+ sc16is7xx_port_update(&one->port, SC16IS7XX_MCR_REG,
+ SC16IS7XX_MCR_LOOP_BIT,
+ (one->port.mctrl & TIOCM_LOOP) ?
+ SC16IS7XX_MCR_LOOP_BIT : 0);
+}
+
+static void sc16is7xx_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
+
+ schedule_work(&one->md_work);
+}
+
+static void sc16is7xx_break_ctl(struct uart_port *port, int break_state)
+{
+ sc16is7xx_port_update(port, SC16IS7XX_LCR_REG,
+ SC16IS7XX_LCR_TXBREAK_BIT,
+ break_state ? SC16IS7XX_LCR_TXBREAK_BIT : 0);
+}
+
+static void sc16is7xx_set_termios(struct uart_port *port,
+ struct ktermios *termios,
+ struct ktermios *old)
+{
+ struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+ unsigned int lcr, flow = 0;
+ int baud;
+
+ /* Mask termios capabilities we don't support */
+ termios->c_cflag &= ~CMSPAR;
+
+ /* Word size */
+ switch (termios->c_cflag & CSIZE) {
+ case CS5:
+ lcr = SC16IS7XX_LCR_WORD_LEN_5;
+ break;
+ case CS6:
+ lcr = SC16IS7XX_LCR_WORD_LEN_6;
+ break;
+ case CS7:
+ lcr = SC16IS7XX_LCR_WORD_LEN_7;
+ break;
+ case CS8:
+ lcr = SC16IS7XX_LCR_WORD_LEN_8;
+ break;
+ default:
+ lcr = SC16IS7XX_LCR_WORD_LEN_8;
+ termios->c_cflag &= ~CSIZE;
+ termios->c_cflag |= CS8;
+ break;
+ }
+
+ /* Parity */
+ if (termios->c_cflag & PARENB) {
+ lcr |= SC16IS7XX_LCR_PARITY_BIT;
+ if (!(termios->c_cflag & PARODD))
+ lcr |= SC16IS7XX_LCR_EVENPARITY_BIT;
+ }
+
+ /* Stop bits */
+ if (termios->c_cflag & CSTOPB)
+ lcr |= SC16IS7XX_LCR_STOPLEN_BIT; /* 2 stops */
+
+ /* Set read status mask */
+ port->read_status_mask = SC16IS7XX_LSR_OE_BIT;
+ if (termios->c_iflag & INPCK)
+ port->read_status_mask |= SC16IS7XX_LSR_PE_BIT |
+ SC16IS7XX_LSR_FE_BIT;
+ if (termios->c_iflag & (BRKINT | PARMRK))
+ port->read_status_mask |= SC16IS7XX_LSR_BI_BIT;
+
+ /* Set status ignore mask */
+ port->ignore_status_mask = 0;
+ if (termios->c_iflag & IGNBRK)
+ port->ignore_status_mask |= SC16IS7XX_LSR_BI_BIT;
+ if (!(termios->c_cflag & CREAD))
+ port->ignore_status_mask |= SC16IS7XX_LSR_BRK_ERROR_MASK;
+
+ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
+ SC16IS7XX_LCR_CONF_MODE_B);
+
+ /* Configure flow control */
+ regcache_cache_bypass(s->regmap, true);
+ sc16is7xx_port_write(port, SC16IS7XX_XON1_REG, termios->c_cc[VSTART]);
+ sc16is7xx_port_write(port, SC16IS7XX_XOFF1_REG, termios->c_cc[VSTOP]);
+ if (termios->c_cflag & CRTSCTS)
+ flow |= SC16IS7XX_EFR_AUTOCTS_BIT |
+ SC16IS7XX_EFR_AUTORTS_BIT;
+ if (termios->c_iflag & IXON)
+ flow |= SC16IS7XX_EFR_SWFLOW3_BIT;
+ if (termios->c_iflag & IXOFF)
+ flow |= SC16IS7XX_EFR_SWFLOW1_BIT;
+
+ sc16is7xx_port_write(port, SC16IS7XX_EFR_REG, flow);
+ regcache_cache_bypass(s->regmap, false);
+
+ /* Update LCR register */
+ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, lcr);
+
+ /* Get baud rate generator configuration */
+ baud = uart_get_baud_rate(port, termios, old,
+ port->uartclk / 16 / 4 / 0xffff,
+ port->uartclk / 16);
+
+ /* Setup baudrate generator */
+ baud = sc16is7xx_set_baud(port, baud);
+
+ /* Update timeout according to new baud rate */
+ uart_update_timeout(port, termios->c_cflag, baud);
+}
+
+static void sc16is7xx_config_rs485(struct uart_port *port,
+ struct serial_rs485 *rs485)
+{
+ struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
+
+ one->rs485 = *rs485;
+
+ if (one->rs485.flags & SER_RS485_ENABLED) {
+ sc16is7xx_port_update(port, SC16IS7XX_EFCR_REG,
+ SC16IS7XX_EFCR_AUTO_RS485_BIT,
+ SC16IS7XX_EFCR_AUTO_RS485_BIT);
+ } else {
+ sc16is7xx_port_update(port, SC16IS7XX_EFCR_REG,
+ SC16IS7XX_EFCR_AUTO_RS485_BIT,
+ 0);
+ }
+}
+
+static int sc16is7xx_ioctl(struct uart_port *port, unsigned int cmd,
+ unsigned long arg)
+{
+#if defined(TIOCSRS485) && defined(TIOCGRS485)
+ struct serial_rs485 rs485;
+
+ switch (cmd) {
+ case TIOCSRS485:
+ if (copy_from_user(&rs485, (void __user *)arg, sizeof(rs485)))
+ return -EFAULT;
+
+ sc16is7xx_config_rs485(port, &rs485);
+ return 0;
+ case TIOCGRS485:
+ if (copy_to_user((void __user *)arg,
+ &(to_sc16is7xx_one(port, port)->rs485),
+ sizeof(rs485)))
+ return -EFAULT;
+ return 0;
+ default:
+ break;
+ }
+#endif
+
+ return -ENOIOCTLCMD;
+}
+
+static int sc16is7xx_startup(struct uart_port *port)
+{
+ struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+ unsigned int val;
+
+ sc16is7xx_power(port, 1);
+
+ /* Reset FIFOs*/
+ val = SC16IS7XX_FCR_RXRESET_BIT | SC16IS7XX_FCR_TXRESET_BIT;
+ sc16is7xx_port_write(port, SC16IS7XX_FCR_REG, val);
+ udelay(5);
+ sc16is7xx_port_write(port, SC16IS7XX_FCR_REG,
+ SC16IS7XX_FCR_FIFO_BIT);
+
+ /* Enable EFR */
+ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG,
+ SC16IS7XX_LCR_CONF_MODE_B);
+
+ regcache_cache_bypass(s->regmap, true);
+
+ /* Enable write access to enhanced features and internal clock div */
+ sc16is7xx_port_write(port, SC16IS7XX_EFR_REG,
+ SC16IS7XX_EFR_ENABLE_BIT);
+
+ /* Enable TCR/TLR */
+ sc16is7xx_port_update(port, SC16IS7XX_MCR_REG,
+ SC16IS7XX_MCR_TCRTLR_BIT,
+ SC16IS7XX_MCR_TCRTLR_BIT);
+
+ /* Configure flow control levels */
+ /* Flow control halt level 48, resume level 24 */
+ sc16is7xx_port_write(port, SC16IS7XX_TCR_REG,
+ SC16IS7XX_TCR_RX_RESUME(24) |
+ SC16IS7XX_TCR_RX_HALT(48));
+
+ regcache_cache_bypass(s->regmap, false);
+
+ /* Now, initialize the UART */
+ sc16is7xx_port_write(port, SC16IS7XX_LCR_REG, SC16IS7XX_LCR_WORD_LEN_8);
+
+ /* Enable the Rx and Tx FIFO */
+ sc16is7xx_port_update(port, SC16IS7XX_EFCR_REG,
+ SC16IS7XX_EFCR_RXDISABLE_BIT |
+ SC16IS7XX_EFCR_TXDISABLE_BIT,
+ 0);
+
+ sc16is7xx_port_update(port, SC16IS7XX_EFCR_REG,
+ SC16IS7XX_EFCR_AUTO_RS485_BIT,
+ SC16IS7XX_EFCR_AUTO_RS485_BIT);
+
+ /* Enable RX, TX, CTS change interrupts */
+ val = SC16IS7XX_IER_RDI_BIT | SC16IS7XX_IER_THRI_BIT |
+ SC16IS7XX_IER_CTSI_BIT;
+ sc16is7xx_port_write(port, SC16IS7XX_IER_REG, val);
+
+ return 0;
+}
+
+static void sc16is7xx_shutdown(struct uart_port *port)
+{
+ /* Disable all interrupts */
+ sc16is7xx_port_write(port, SC16IS7XX_IER_REG, 0);
+ /* Disable TX/RX */
+ sc16is7xx_port_write(port, SC16IS7XX_EFCR_REG,
+ SC16IS7XX_EFCR_RXDISABLE_BIT |
+ SC16IS7XX_EFCR_TXDISABLE_BIT);
+
+ sc16is7xx_power(port, 0);
+}
+
+static const char *sc16is7xx_type(struct uart_port *port)
+{
+ struct sc16is7xx_port *s = dev_get_drvdata(port->dev);
+
+ return (port->type == PORT_SC16IS7XX) ? s->devtype->name : NULL;
+}
+
+static int sc16is7xx_request_port(struct uart_port *port)
+{
+ /* Do nothing */
+ return 0;
+}
+
+static void sc16is7xx_config_port(struct uart_port *port, int flags)
+{
+ if (flags & UART_CONFIG_TYPE)
+ port->type = PORT_SC16IS7XX;
+}
+
+static int sc16is7xx_verify_port(struct uart_port *port,
+ struct serial_struct *s)
+{
+ if ((s->type != PORT_UNKNOWN) && (s->type != PORT_SC16IS7XX))
+ return -EINVAL;
+ if (s->irq != port->irq)
+ return -EINVAL;
+
+ return 0;
+}
+
+static void sc16is7xx_pm(struct uart_port *port, unsigned int state,
+ unsigned int oldstate)
+{
+ sc16is7xx_power(port, (state == UART_PM_STATE_ON) ? 1 : 0);
+}
+
+static void sc16is7xx_null_void(struct uart_port *port)
+{
+ /* Do nothing */
+}
+
+static const struct uart_ops sc16is7xx_ops = {
+ .tx_empty = sc16is7xx_tx_empty,
+ .set_mctrl = sc16is7xx_set_mctrl,
+ .get_mctrl = sc16is7xx_get_mctrl,
+ .stop_tx = sc16is7xx_stop_tx,
+ .start_tx = sc16is7xx_start_tx,
+ .stop_rx = sc16is7xx_stop_rx,
+ .enable_ms = sc16is7xx_null_void,
+ .break_ctl = sc16is7xx_break_ctl,
+ .startup = sc16is7xx_startup,
+ .shutdown = sc16is7xx_shutdown,
+ .set_termios = sc16is7xx_set_termios,
+ .type = sc16is7xx_type,
+ .request_port = sc16is7xx_request_port,
+ .release_port = sc16is7xx_null_void,
+ .config_port = sc16is7xx_config_port,
+ .verify_port = sc16is7xx_verify_port,
+ .ioctl = sc16is7xx_ioctl,
+ .pm = sc16is7xx_pm,
+};
+
+#ifdef CONFIG_GPIOLIB
+static int sc16is7xx_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ unsigned int val;
+ struct sc16is7xx_port *s = container_of(chip, struct sc16is7xx_port,
+ gpio);
+ struct uart_port *port = &s->p[0].port;
+
+ val = sc16is7xx_port_read(port, SC16IS7XX_IOSTATE_REG);
+
+ return !!(val & BIT(offset));
+}
+
+static void sc16is7xx_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
+{
+ struct sc16is7xx_port *s = container_of(chip, struct sc16is7xx_port,
+ gpio);
+ struct uart_port *port = &s->p[0].port;
+
+ sc16is7xx_port_update(port, SC16IS7XX_IOSTATE_REG, BIT(offset),
+ val ? BIT(offset) : 0);
+}
+
+static int sc16is7xx_gpio_direction_input(struct gpio_chip *chip,
+ unsigned offset)
+{
+ struct sc16is7xx_port *s = container_of(chip, struct sc16is7xx_port,
+ gpio);
+ struct uart_port *port = &s->p[0].port;
+
+ sc16is7xx_port_update(port, SC16IS7XX_IODIR_REG, BIT(offset), 0);
+
+ return 0;
+}
+
+static int sc16is7xx_gpio_direction_output(struct gpio_chip *chip,
+ unsigned offset, int val)
+{
+ struct sc16is7xx_port *s = container_of(chip, struct sc16is7xx_port,
+ gpio);
+ struct uart_port *port = &s->p[0].port;
+
+ sc16is7xx_port_update(port, SC16IS7XX_IOSTATE_REG, BIT(offset),
+ val ? BIT(offset) : 0);
+ sc16is7xx_port_update(port, SC16IS7XX_IODIR_REG, BIT(offset),
+ BIT(offset));
+
+ return 0;
+}
+#endif
+
+static int sc16is7xx_probe(struct device *dev,
+ struct sc16is7xx_devtype *devtype,
+ struct regmap *regmap, int irq, unsigned long flags)
+{
+ unsigned long freq, *pfreq = dev_get_platdata(dev);
+ struct clk *clk;
+ int i, ret;
+ struct sc16is7xx_port *s;
+
+ if (IS_ERR(regmap))
+ return PTR_ERR(regmap);
+
+ /* Alloc port structure */
+ s = devm_kzalloc(dev, sizeof(*s) +
+ sizeof(struct sc16is7xx_one) * devtype->nr_uart,
+ GFP_KERNEL);
+ if (!s) {
+ dev_err(dev, "Error allocating port structure\n");
+ return -ENOMEM;
+ }
+
+ clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(clk)) {
+ if (pfreq)
+ freq = *pfreq;
+ else
+ return PTR_ERR(clk);
+ } else {
+ freq = clk_get_rate(clk);
+ }
+
+ s->regmap = regmap;
+ s->devtype = devtype;
+ dev_set_drvdata(dev, s);
+
+ /* Register UART driver */
+ s->uart.owner = THIS_MODULE;
+ s->uart.dev_name = "ttySC";
+ s->uart.nr = devtype->nr_uart;
+ ret = uart_register_driver(&s->uart);
+ if (ret) {
+ dev_err(dev, "Registering UART driver failed\n");
+ goto out_clk;
+ }
+
+#ifdef CONFIG_GPIOLIB
+ if (devtype->nr_gpio) {
+ /* Setup GPIO cotroller */
+ s->gpio.owner = THIS_MODULE;
+ s->gpio.dev = dev;
+ s->gpio.label = dev_name(dev);
+ s->gpio.direction_input = sc16is7xx_gpio_direction_input;
+ s->gpio.get = sc16is7xx_gpio_get;
+ s->gpio.direction_output = sc16is7xx_gpio_direction_output;
+ s->gpio.set = sc16is7xx_gpio_set;
+ s->gpio.base = -1;
+ s->gpio.ngpio = devtype->nr_gpio;
+ s->gpio.can_sleep = 1;
+ ret = gpiochip_add(&s->gpio);
+ if (ret)
+ goto out_uart;
+ }
+#endif
+
+ mutex_init(&s->mutex);
+
+ for (i = 0; i < devtype->nr_uart; ++i) {
+ /* Initialize port data */
+ s->p[i].port.line = i;
+ s->p[i].port.dev = dev;
+ s->p[i].port.irq = irq;
+ s->p[i].port.type = PORT_SC16IS7XX;
+ s->p[i].port.fifosize = SC16IS7XX_FIFO_SIZE;
+ s->p[i].port.flags = UPF_FIXED_TYPE | UPF_LOW_LATENCY;
+ s->p[i].port.iotype = UPIO_PORT;
+ s->p[i].port.uartclk = freq;
+ s->p[i].port.ops = &sc16is7xx_ops;
+ /* Disable all interrupts */
+ sc16is7xx_port_write(&s->p[i].port, SC16IS7XX_IER_REG, 0);
+ /* Disable TX/RX */
+ sc16is7xx_port_write(&s->p[i].port, SC16IS7XX_EFCR_REG,
+ SC16IS7XX_EFCR_RXDISABLE_BIT |
+ SC16IS7XX_EFCR_TXDISABLE_BIT);
+ /* Initialize queue for start TX */
+ INIT_WORK(&s->p[i].tx_work, sc16is7xx_wq_proc);
+ /* Initialize queue for changing mode */
+ INIT_WORK(&s->p[i].md_work, sc16is7xx_md_proc);
+ /* Register port */
+ uart_add_one_port(&s->uart, &s->p[i].port);
+ /* Go to suspend mode */
+ sc16is7xx_power(&s->p[i].port, 0);
+ }
+
+ /* Setup interrupt */
+ ret = devm_request_threaded_irq(dev, irq, NULL, sc16is7xx_ist,
+ IRQF_ONESHOT | flags, dev_name(dev), s);
+ if (!ret)
+ return 0;
+
+ mutex_destroy(&s->mutex);
+
+#ifdef CONFIG_GPIOLIB
+ if (devtype->nr_gpio)
+ WARN_ON(gpiochip_remove(&s->gpio));
+
+out_uart:
+#endif
+ uart_unregister_driver(&s->uart);
+
+out_clk:
+ if (!IS_ERR(s->clk))
+ clk_disable_unprepare(s->clk);
+
+ return ret;
+}
+
+static int sc16is7xx_remove(struct device *dev)
+{
+ struct sc16is7xx_port *s = dev_get_drvdata(dev);
+ int i, ret = 0;
+
+#ifdef CONFIG_GPIOLIB
+ if (s->devtype->nr_gpio) {
+ ret = gpiochip_remove(&s->gpio);
+ if (ret)
+ return ret;
+ }
+#endif
+
+ for (i = 0; i < s->uart.nr; i++) {
+ cancel_work_sync(&s->p[i].tx_work);
+ cancel_work_sync(&s->p[i].md_work);
+ uart_remove_one_port(&s->uart, &s->p[i].port);
+ sc16is7xx_power(&s->p[i].port, 0);
+ }
+
+ mutex_destroy(&s->mutex);
+ uart_unregister_driver(&s->uart);
+ if (!IS_ERR(s->clk))
+ clk_disable_unprepare(s->clk);
+
+ return ret;
+}
+
+static const struct of_device_id __maybe_unused sc16is7xx_dt_ids[] = {
+ { .compatible = "nxp,sc16is740", .data = &sc16is74x_devtype, },
+ { .compatible = "nxp,sc16is741", .data = &sc16is74x_devtype, },
+ { .compatible = "nxp,sc16is750", .data = &sc16is750_devtype, },
+ { .compatible = "nxp,sc16is752", .data = &sc16is752_devtype, },
+ { .compatible = "nxp,sc16is760", .data = &sc16is760_devtype, },
+ { .compatible = "nxp,sc16is762", .data = &sc16is762_devtype, },
+ { }
+};
+MODULE_DEVICE_TABLE(of, sc16is7xx_dt_ids);
+
+static struct regmap_config regcfg = {
+ .reg_bits = 7,
+ .pad_bits = 1,
+ .val_bits = 8,
+ .cache_type = REGCACHE_RBTREE,
+ .writeable_reg = sc16is7xx_regmap_writeable,
+ .volatile_reg = sc16is7xx_regmap_volatile,
+ .precious_reg = sc16is7xx_regmap_precious,
+};
+
+#ifdef CONFIG_REGMAP_I2C
+static int sc16is7xx_i2c_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ struct sc16is7xx_devtype *devtype;
+ unsigned long flags = 0;
+ struct regmap *regmap;
+
+ if (i2c->dev.of_node) {
+ const struct of_device_id *of_id =
+ of_match_device(sc16is7xx_dt_ids, &i2c->dev);
+
+ devtype = (struct sc16is7xx_devtype *)of_id->data;
+ } else {
+ devtype = (struct sc16is7xx_devtype *)id->driver_data;
+ flags = IRQF_TRIGGER_FALLING;
+ }
+
+ regcfg.max_register = (0xf << SC16IS7XX_REG_SHIFT) |
+ (devtype->nr_uart - 1);
+ regmap = devm_regmap_init_i2c(i2c, &regcfg);
+
+ return sc16is7xx_probe(&i2c->dev, devtype, regmap, i2c->irq, flags);
+}
+
+static int sc16is7xx_i2c_remove(struct i2c_client *client)
+{
+ return sc16is7xx_remove(&client->dev);
+}
+
+static const struct i2c_device_id sc16is7xx_i2c_id_table[] = {
+ { "sc16is74x", (kernel_ulong_t)&sc16is74x_devtype, },
+ { "sc16is750", (kernel_ulong_t)&sc16is750_devtype, },
+ { "sc16is752", (kernel_ulong_t)&sc16is752_devtype, },
+ { "sc16is760", (kernel_ulong_t)&sc16is760_devtype, },
+ { "sc16is762", (kernel_ulong_t)&sc16is762_devtype, },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, sc16is7xx_i2c_id_table);
+
+static struct i2c_driver sc16is7xx_i2c_uart_driver = {
+ .driver = {
+ .name = SC16IS7XX_NAME,
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(sc16is7xx_dt_ids),
+ },
+ .probe = sc16is7xx_i2c_probe,
+ .remove = sc16is7xx_i2c_remove,
+ .id_table = sc16is7xx_i2c_id_table,
+};
+module_i2c_driver(sc16is7xx_i2c_uart_driver);
+MODULE_ALIAS("i2c:sc16is7xx");
+#endif
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jon Ringle <jringle@xxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("SC16IS7XX serial driver");
diff --git a/include/uapi/linux/serial_core.h b/include/uapi/linux/serial_core.h
index b47dba2..a37c79a 100644
--- a/include/uapi/linux/serial_core.h
+++ b/include/uapi/linux/serial_core.h
@@ -238,4 +238,7 @@
/* Tilera TILE-Gx UART */
#define PORT_TILEGX 106

+/* SC16IS74xx */
+#define PORT_SC16IS7XX 107
+
#endif /* _UAPILINUX_SERIAL_CORE_H */
--
1.8.5.4

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