diff options
Diffstat (limited to 'drivers/tty/serial/vt8500_serial.c')
| -rw-r--r-- | drivers/tty/serial/vt8500_serial.c | 111 |
1 files changed, 75 insertions, 36 deletions
diff --git a/drivers/tty/serial/vt8500_serial.c b/drivers/tty/serial/vt8500_serial.c index 322bf56c0d8..15ad6fcda88 100644 --- a/drivers/tty/serial/vt8500_serial.c +++ b/drivers/tty/serial/vt8500_serial.c @@ -1,6 +1,4 @@ /* - * drivers/serial/vt8500_serial.c - * * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com> * * Based on msm_serial.c, which is: @@ -36,6 +34,8 @@ #include <linux/slab.h> #include <linux/clk.h> #include <linux/platform_device.h> +#include <linux/of.h> +#include <linux/err.h> /* * UART Register offsets @@ -78,6 +78,8 @@ #define RX_FIFO_INTS (RXFAF | RXFF | RXOVER | PER | FER | RXTOUT) #define TX_FIFO_INTS (TXFAE | TXFE | TXUDR) +#define VT8500_MAX_PORTS 6 + struct vt8500_port { struct uart_port uart; char name[16]; @@ -85,6 +87,13 @@ struct vt8500_port { unsigned int ier; }; +/* + * we use this variable to keep track of which ports + * have been allocated as we can't use pdev->id in + * devicetree + */ +static unsigned long vt8500_ports_in_use; + static inline void vt8500_write(struct uart_port *port, unsigned int val, unsigned int off) { @@ -128,22 +137,14 @@ static void vt8500_enable_ms(struct uart_port *port) static void handle_rx(struct uart_port *port) { - struct tty_struct *tty = tty_port_tty_get(&port->state->port); - if (!tty) { - /* Discard data: no tty available */ - int count = (vt8500_read(port, VT8500_URFIDX) & 0x1f00) >> 8; - u16 ch; - while (count--) - ch = readw(port->membase + VT8500_RXFIFO); - return; - } + struct tty_port *tport = &port->state->port; /* * Handle overrun */ if ((vt8500_read(port, VT8500_URISR) & RXOVER)) { port->icount.overrun++; - tty_insert_flip_char(tty, 0, TTY_OVERRUN); + tty_insert_flip_char(tport, 0, TTY_OVERRUN); } /* and now the main RX loop */ @@ -166,11 +167,12 @@ static void handle_rx(struct uart_port *port) port->icount.rx++; if (!uart_handle_sysrq_char(port, c)) - tty_insert_flip_char(tty, c, flag); + tty_insert_flip_char(tport, c, flag); } - tty_flip_buffer_push(tty); - tty_kref_put(tty); + spin_unlock(&port->lock); + tty_flip_buffer_push(tport); + spin_lock(&port->lock); } static void handle_tx(struct uart_port *port) @@ -433,7 +435,7 @@ static int vt8500_verify_port(struct uart_port *port, return 0; } -static struct vt8500_port *vt8500_uart_ports[4]; +static struct vt8500_port *vt8500_uart_ports[VT8500_MAX_PORTS]; static struct uart_driver vt8500_uart_driver; #ifdef CONFIG_SERIAL_VT8500_CONSOLE @@ -546,72 +548,109 @@ static struct uart_driver vt8500_uart_driver = { .cons = VT8500_CONSOLE, }; -static int __init vt8500_serial_probe(struct platform_device *pdev) +static int vt8500_serial_probe(struct platform_device *pdev) { struct vt8500_port *vt8500_port; struct resource *mmres, *irqres; + struct device_node *np = pdev->dev.of_node; int ret; + int port; mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0); irqres = platform_get_resource(pdev, IORESOURCE_IRQ, 0); if (!mmres || !irqres) return -ENODEV; - vt8500_port = kzalloc(sizeof(struct vt8500_port), GFP_KERNEL); + if (np) { + port = of_alias_get_id(np, "serial"); + if (port >= VT8500_MAX_PORTS) + port = -1; + } else { + port = -1; + } + + if (port < 0) { + /* calculate the port id */ + port = find_first_zero_bit(&vt8500_ports_in_use, + sizeof(vt8500_ports_in_use)); + } + + if (port >= VT8500_MAX_PORTS) + return -ENODEV; + + /* reserve the port id */ + if (test_and_set_bit(port, &vt8500_ports_in_use)) { + /* port already in use - shouldn't really happen */ + return -EBUSY; + } + + vt8500_port = devm_kzalloc(&pdev->dev, sizeof(struct vt8500_port), + GFP_KERNEL); if (!vt8500_port) return -ENOMEM; + vt8500_port->uart.membase = devm_ioremap_resource(&pdev->dev, mmres); + if (IS_ERR(vt8500_port->uart.membase)) + return PTR_ERR(vt8500_port->uart.membase); + + vt8500_port->clk = of_clk_get(pdev->dev.of_node, 0); + if (IS_ERR(vt8500_port->clk)) { + dev_err(&pdev->dev, "failed to get clock\n"); + return -EINVAL; + } + + ret = clk_prepare_enable(vt8500_port->clk); + if (ret) { + dev_err(&pdev->dev, "failed to enable clock\n"); + return ret; + } + vt8500_port->uart.type = PORT_VT8500; vt8500_port->uart.iotype = UPIO_MEM; vt8500_port->uart.mapbase = mmres->start; vt8500_port->uart.irq = irqres->start; vt8500_port->uart.fifosize = 16; vt8500_port->uart.ops = &vt8500_uart_pops; - vt8500_port->uart.line = pdev->id; + vt8500_port->uart.line = port; vt8500_port->uart.dev = &pdev->dev; vt8500_port->uart.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF; - vt8500_port->uart.uartclk = 24000000; + + vt8500_port->uart.uartclk = clk_get_rate(vt8500_port->clk); snprintf(vt8500_port->name, sizeof(vt8500_port->name), "VT8500 UART%d", pdev->id); - vt8500_port->uart.membase = ioremap(mmres->start, - mmres->end - mmres->start + 1); - if (!vt8500_port->uart.membase) { - ret = -ENOMEM; - goto err; - } - - vt8500_uart_ports[pdev->id] = vt8500_port; + vt8500_uart_ports[port] = vt8500_port; uart_add_one_port(&vt8500_uart_driver, &vt8500_port->uart); platform_set_drvdata(pdev, vt8500_port); return 0; - -err: - kfree(vt8500_port); - return ret; } -static int __devexit vt8500_serial_remove(struct platform_device *pdev) +static int vt8500_serial_remove(struct platform_device *pdev) { struct vt8500_port *vt8500_port = platform_get_drvdata(pdev); - platform_set_drvdata(pdev, NULL); + clk_disable_unprepare(vt8500_port->clk); uart_remove_one_port(&vt8500_uart_driver, &vt8500_port->uart); - kfree(vt8500_port); return 0; } +static const struct of_device_id wmt_dt_ids[] = { + { .compatible = "via,vt8500-uart", }, + {} +}; + static struct platform_driver vt8500_platform_driver = { .probe = vt8500_serial_probe, .remove = vt8500_serial_remove, .driver = { .name = "vt8500_serial", .owner = THIS_MODULE, + .of_match_table = wmt_dt_ids, }, }; @@ -645,4 +684,4 @@ module_exit(vt8500_serial_exit); MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>"); MODULE_DESCRIPTION("Driver for vt8500 serial device"); -MODULE_LICENSE("GPL"); +MODULE_LICENSE("GPL v2"); |