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path: root/drivers/tty/serial/sc16is7xx.c
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Diffstat (limited to 'drivers/tty/serial/sc16is7xx.c')
-rw-r--r--drivers/tty/serial/sc16is7xx.c170
1 files changed, 131 insertions, 39 deletions
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 2e7e7c409cf2..f61d98e09dc3 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -236,7 +236,8 @@
/* IOControl register bits (Only 750/760) */
#define SC16IS7XX_IOCONTROL_LATCH_BIT (1 << 0) /* Enable input latching */
-#define SC16IS7XX_IOCONTROL_MODEM_BIT (1 << 1) /* Enable GPIO[7:4] as modem pins */
+#define SC16IS7XX_IOCONTROL_MODEM_A_BIT (1 << 1) /* Enable GPIO[7:4] as modem A pins */
+#define SC16IS7XX_IOCONTROL_MODEM_B_BIT (1 << 2) /* Enable GPIO[3:0] as modem B pins */
#define SC16IS7XX_IOCONTROL_SRESET_BIT (1 << 3) /* Software Reset */
/* EFCR register bits */
@@ -301,12 +302,12 @@
/* Misc definitions */
#define SC16IS7XX_FIFO_SIZE (64)
#define SC16IS7XX_REG_SHIFT 2
+#define SC16IS7XX_GPIOS_PER_BANK 4
struct sc16is7xx_devtype {
char name[10];
int nr_gpio;
int nr_uart;
- int has_mctrl;
};
#define SC16IS7XX_RECONF_MD (1 << 0)
@@ -336,7 +337,9 @@ struct sc16is7xx_port {
struct clk *clk;
#ifdef CONFIG_GPIOLIB
struct gpio_chip gpio;
+ unsigned long gpio_valid_mask;
#endif
+ u8 mctrl_mask;
unsigned char buf[SC16IS7XX_FIFO_SIZE];
struct kthread_worker kworker;
struct task_struct *kworker_task;
@@ -447,35 +450,30 @@ static const struct sc16is7xx_devtype sc16is74x_devtype = {
.name = "SC16IS74X",
.nr_gpio = 0,
.nr_uart = 1,
- .has_mctrl = 0,
};
static const struct sc16is7xx_devtype sc16is750_devtype = {
.name = "SC16IS750",
- .nr_gpio = 4,
+ .nr_gpio = 8,
.nr_uart = 1,
- .has_mctrl = 1,
};
static const struct sc16is7xx_devtype sc16is752_devtype = {
.name = "SC16IS752",
- .nr_gpio = 0,
+ .nr_gpio = 8,
.nr_uart = 2,
- .has_mctrl = 1,
};
static const struct sc16is7xx_devtype sc16is760_devtype = {
.name = "SC16IS760",
- .nr_gpio = 4,
+ .nr_gpio = 8,
.nr_uart = 1,
- .has_mctrl = 1,
};
static const struct sc16is7xx_devtype sc16is762_devtype = {
.name = "SC16IS762",
- .nr_gpio = 0,
+ .nr_gpio = 8,
.nr_uart = 2,
- .has_mctrl = 1,
};
static bool sc16is7xx_regmap_volatile(struct device *dev, unsigned int reg)
@@ -488,6 +486,7 @@ static bool sc16is7xx_regmap_volatile(struct device *dev, unsigned int reg)
case SC16IS7XX_TXLVL_REG:
case SC16IS7XX_RXLVL_REG:
case SC16IS7XX_IOSTATE_REG:
+ case SC16IS7XX_IOCONTROL_REG:
return true;
default:
break;
@@ -578,8 +577,9 @@ 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;
+ unsigned int lsr = 0, bytes_read, i;
bool read_lsr = (iir == SC16IS7XX_IIR_RLSE_SRC) ? true : false;
+ u8 ch, flag;
if (unlikely(rxlen >= sizeof(s->buf))) {
dev_warn_ratelimited(port->dev,
@@ -1342,14 +1342,113 @@ static int sc16is7xx_gpio_direction_output(struct gpio_chip *chip,
state |= BIT(offset);
else
state &= ~BIT(offset);
- sc16is7xx_port_write(port, SC16IS7XX_IOSTATE_REG, state);
+
+ /*
+ * If we write IOSTATE first, and then IODIR, the output value is not
+ * transferred to the corresponding I/O pin.
+ * The datasheet states that each register bit will be transferred to
+ * the corresponding I/O pin programmed as output when writing to
+ * IOSTATE. Therefore, configure direction first with IODIR, and then
+ * set value after with IOSTATE.
+ */
sc16is7xx_port_update(port, SC16IS7XX_IODIR_REG, BIT(offset),
BIT(offset));
+ sc16is7xx_port_write(port, SC16IS7XX_IOSTATE_REG, state);
return 0;
}
+
+static int sc16is7xx_gpio_init_valid_mask(struct gpio_chip *chip,
+ unsigned long *valid_mask,
+ unsigned int ngpios)
+{
+ struct sc16is7xx_port *s = gpiochip_get_data(chip);
+
+ *valid_mask = s->gpio_valid_mask;
+
+ return 0;
+}
+
+static int sc16is7xx_setup_gpio_chip(struct sc16is7xx_port *s)
+{
+ struct device *dev = s->p[0].port.dev;
+
+ if (!s->devtype->nr_gpio)
+ return 0;
+
+ switch (s->mctrl_mask) {
+ case 0:
+ s->gpio_valid_mask = GENMASK(7, 0);
+ break;
+ case SC16IS7XX_IOCONTROL_MODEM_A_BIT:
+ s->gpio_valid_mask = GENMASK(3, 0);
+ break;
+ case SC16IS7XX_IOCONTROL_MODEM_B_BIT:
+ s->gpio_valid_mask = GENMASK(7, 4);
+ break;
+ default:
+ break;
+ }
+
+ if (s->gpio_valid_mask == 0)
+ return 0;
+
+ s->gpio.owner = THIS_MODULE;
+ s->gpio.parent = dev;
+ s->gpio.label = dev_name(dev);
+ s->gpio.init_valid_mask = sc16is7xx_gpio_init_valid_mask;
+ 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 = s->devtype->nr_gpio;
+ s->gpio.can_sleep = 1;
+
+ return gpiochip_add_data(&s->gpio, s);
+}
#endif
+/*
+ * Configure ports designated to operate as modem control lines.
+ */
+static int sc16is7xx_setup_mctrl_ports(struct sc16is7xx_port *s)
+{
+ int i;
+ int ret;
+ int count;
+ u32 mctrl_port[2];
+ struct device *dev = s->p[0].port.dev;
+
+ count = device_property_count_u32(dev, "nxp,modem-control-line-ports");
+ if (count < 0 || count > ARRAY_SIZE(mctrl_port))
+ return 0;
+
+ ret = device_property_read_u32_array(dev, "nxp,modem-control-line-ports",
+ mctrl_port, count);
+ if (ret)
+ return ret;
+
+ s->mctrl_mask = 0;
+
+ for (i = 0; i < count; i++) {
+ /* Use GPIO lines as modem control lines */
+ if (mctrl_port[i] == 0)
+ s->mctrl_mask |= SC16IS7XX_IOCONTROL_MODEM_A_BIT;
+ else if (mctrl_port[i] == 1)
+ s->mctrl_mask |= SC16IS7XX_IOCONTROL_MODEM_B_BIT;
+ }
+
+ if (s->mctrl_mask)
+ regmap_update_bits(
+ s->regmap,
+ SC16IS7XX_IOCONTROL_REG << SC16IS7XX_REG_SHIFT,
+ SC16IS7XX_IOCONTROL_MODEM_A_BIT |
+ SC16IS7XX_IOCONTROL_MODEM_B_BIT, s->mctrl_mask);
+
+ return 0;
+}
+
static const struct serial_rs485 sc16is7xx_rs485_supported = {
.flags = SER_RS485_ENABLED | SER_RS485_RTS_AFTER_SEND,
.delay_rts_before_send = 1,
@@ -1436,6 +1535,12 @@ static int sc16is7xx_probe(struct device *dev,
s->p[i].port.fifosize = SC16IS7XX_FIFO_SIZE;
s->p[i].port.flags = UPF_FIXED_TYPE | UPF_LOW_LATENCY;
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.iotype = UPIO_PORT;
s->p[i].port.uartclk = freq;
s->p[i].port.rs485_config = sc16is7xx_config_rs485;
@@ -1449,6 +1554,10 @@ static int sc16is7xx_probe(struct device *dev,
goto out_ports;
}
+ ret = uart_get_rs485_mode(&s->p[i].port);
+ if (ret)
+ goto out_ports;
+
/* Disable all interrupts */
sc16is7xx_port_write(&s->p[i].port, SC16IS7XX_IER_REG, 0);
/* Disable TX/RX */
@@ -1456,12 +1565,6 @@ static int sc16is7xx_probe(struct device *dev,
SC16IS7XX_EFCR_RXDISABLE_BIT |
SC16IS7XX_EFCR_TXDISABLE_BIT);
- /* Use GPIO lines as modem status registers */
- if (devtype->has_mctrl)
- sc16is7xx_port_write(&s->p[i].port,
- SC16IS7XX_IOCONTROL_REG,
- SC16IS7XX_IOCONTROL_MODEM_BIT);
-
/* Initialize kthread work structs */
kthread_init_work(&s->p[i].tx_work, sc16is7xx_tx_proc);
kthread_init_work(&s->p[i].reg_work, sc16is7xx_reg_proc);
@@ -1499,23 +1602,14 @@ static int sc16is7xx_probe(struct device *dev,
s->p[u].irda_mode = true;
}
+ ret = sc16is7xx_setup_mctrl_ports(s);
+ if (ret)
+ goto out_ports;
+
#ifdef CONFIG_GPIOLIB
- if (devtype->nr_gpio) {
- /* Setup GPIO cotroller */
- s->gpio.owner = THIS_MODULE;
- s->gpio.parent = 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_data(&s->gpio, s);
- if (ret)
- goto out_thread;
- }
+ ret = sc16is7xx_setup_gpio_chip(s);
+ if (ret)
+ goto out_ports;
#endif
/*
@@ -1538,10 +1632,8 @@ static int sc16is7xx_probe(struct device *dev,
return 0;
#ifdef CONFIG_GPIOLIB
- if (devtype->nr_gpio)
+ if (s->gpio_valid_mask)
gpiochip_remove(&s->gpio);
-
-out_thread:
#endif
out_ports:
@@ -1564,7 +1656,7 @@ static void sc16is7xx_remove(struct device *dev)
int i;
#ifdef CONFIG_GPIOLIB
- if (s->devtype->nr_gpio)
+ if (s->gpio_valid_mask)
gpiochip_remove(&s->gpio);
#endif