diff options
Diffstat (limited to 'drivers/serial')
| -rw-r--r-- | drivers/serial/amba-pl010.c | 39 |
1 files changed, 37 insertions, 2 deletions
diff --git a/drivers/serial/amba-pl010.c b/drivers/serial/amba-pl010.c index ea49aafd66b..1a9a24b8263 100644 --- a/drivers/serial/amba-pl010.c +++ b/drivers/serial/amba-pl010.c @@ -48,6 +48,7 @@ #include <linux/serial.h> #include <linux/amba/bus.h> #include <linux/amba/serial.h> +#include <linux/clk.h> #include <asm/io.h> @@ -70,6 +71,7 @@ */ struct uart_amba_port { struct uart_port port; + struct clk *clk; struct amba_device *dev; struct amba_pl010_data *data; unsigned int old_status; @@ -313,11 +315,20 @@ static int pl010_startup(struct uart_port *port) int retval; /* + * Try to enable the clock producer. + */ + retval = clk_enable(uap->clk); + if (retval) + goto out; + + uap->port.uartclk = clk_get_rate(uap->clk); + + /* * Allocate the IRQ */ retval = request_irq(uap->port.irq, pl010_int, 0, "uart-pl010", uap); if (retval) - return retval; + goto clk_dis; /* * initialise the old status of the modem signals @@ -331,6 +342,11 @@ static int pl010_startup(struct uart_port *port) uap->port.membase + UART010_CR); return 0; + + clk_dis: + clk_disable(uap->clk); + out: + return retval; } static void pl010_shutdown(struct uart_port *port) @@ -351,6 +367,11 @@ static void pl010_shutdown(struct uart_port *port) writel(readb(uap->port.membase + UART010_LCRH) & ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN), uap->port.membase + UART010_LCRH); + + /* + * Shut down the clock producer + */ + clk_disable(uap->clk); } static void @@ -540,6 +561,8 @@ pl010_console_write(struct console *co, const char *s, unsigned int count) struct uart_amba_port *uap = amba_ports[co->index]; unsigned int status, old_cr; + clk_enable(uap->clk); + /* * First save the CR then disable the interrupts */ @@ -557,6 +580,8 @@ pl010_console_write(struct console *co, const char *s, unsigned int count) barrier(); } while (status & UART01x_FR_BUSY); writel(old_cr, uap->port.membase + UART010_CR); + + clk_disable(uap->clk); } static void __init @@ -605,6 +630,8 @@ static int __init pl010_console_setup(struct console *co, char *options) if (!uap) return -ENODEV; + uap->port.uartclk = clk_get_rate(uap->clk); + if (options) uart_parse_options(options, &baud, &parity, &bits, &flow); else @@ -666,12 +693,17 @@ static int pl010_probe(struct amba_device *dev, void *id) goto free; } + uap->clk = clk_get(&dev->dev, "UARTCLK"); + if (IS_ERR(uap->clk)) { + ret = PTR_ERR(uap->clk); + goto unmap; + } + uap->port.dev = &dev->dev; uap->port.mapbase = dev->res.start; uap->port.membase = base; uap->port.iotype = UPIO_MEM; uap->port.irq = dev->irq[0]; - uap->port.uartclk = 14745600; uap->port.fifosize = 16; uap->port.ops = &amba_pl010_pops; uap->port.flags = UPF_BOOT_AUTOCONF; @@ -686,6 +718,8 @@ static int pl010_probe(struct amba_device *dev, void *id) if (ret) { amba_set_drvdata(dev, NULL); amba_ports[i] = NULL; + clk_put(uap->clk); + unmap: iounmap(base); free: kfree(uap); @@ -708,6 +742,7 @@ static int pl010_remove(struct amba_device *dev) amba_ports[i] = NULL; iounmap(uap->port.membase); + clk_put(uap->clk); kfree(uap); return 0; } |