From cdb8612147b7fba751e6fa193f32b09937a7e16b Mon Sep 17 00:00:00 2001 From: John Crispin Date: Thu, 12 Apr 2012 21:21:56 +0200 Subject: [PATCH] watchdog: MIPS: lantiq: implement OF support and minor fixes Add support for OF. We also apply the following small fixes * reduce boiler plate by using devm_request_and_ioremap * sane error path for the clock * move LTQ_RST_CAUSE_WDTRST to a soc specific header file * add a message to show that the driver loaded Signed-off-by: John Crispin Acked-by: Wim Van Sebroeck Cc: linux-watchdog@vger.kernel.org Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/3810/ Signed-off-by: Ralf Baechle --- arch/mips/include/asm/mach-lantiq/lantiq.h | 1 - .../include/asm/mach-lantiq/xway/lantiq_soc.h | 2 + drivers/watchdog/lantiq_wdt.c | 56 +++++++++---------- 3 files changed, 27 insertions(+), 32 deletions(-) diff --git a/arch/mips/include/asm/mach-lantiq/lantiq.h b/arch/mips/include/asm/mach-lantiq/lantiq.h index 6775d2402cd0..64fbc3faad64 100644 --- a/arch/mips/include/asm/mach-lantiq/lantiq.h +++ b/arch/mips/include/asm/mach-lantiq/lantiq.h @@ -49,7 +49,6 @@ extern struct clk *clk_get_io(void); extern unsigned char ltq_boot_select(void); /* find out what caused the last cpu reset */ extern int ltq_reset_cause(void); -#define LTQ_RST_CAUSE_WDTRST 0x20 #define IOPORT_RESOURCE_START 0x10000000 #define IOPORT_RESOURCE_END 0xffffffff diff --git a/arch/mips/include/asm/mach-lantiq/xway/lantiq_soc.h b/arch/mips/include/asm/mach-lantiq/xway/lantiq_soc.h index b5a2acf9156f..d0d40a42327c 100644 --- a/arch/mips/include/asm/mach-lantiq/xway/lantiq_soc.h +++ b/arch/mips/include/asm/mach-lantiq/xway/lantiq_soc.h @@ -133,6 +133,8 @@ extern __iomem void *ltq_cgu_membase; #define LTQ_WDT_BASE_ADDR 0x1F8803F0 #define LTQ_WDT_SIZE 0x10 +#define LTQ_RST_CAUSE_WDTRST 0x20 + /* STP - serial to parallel conversion unit */ #define LTQ_STP_BASE_ADDR 0x1E100BB0 #define LTQ_STP_SIZE 0x40 diff --git a/drivers/watchdog/lantiq_wdt.c b/drivers/watchdog/lantiq_wdt.c index a9593a3a32a0..2e74c3a8ee58 100644 --- a/drivers/watchdog/lantiq_wdt.c +++ b/drivers/watchdog/lantiq_wdt.c @@ -13,14 +13,15 @@ #include #include #include -#include +#include #include #include #include -#include +#include -/* Section 3.4 of the datasheet +/* + * Section 3.4 of the datasheet * The password sequence protects the WDT control register from unintended * write actions, which might cause malfunction of the WDT. * @@ -70,7 +71,8 @@ ltq_wdt_disable(void) { /* write the first password magic */ ltq_w32(LTQ_WDT_PW1, ltq_wdt_membase + LTQ_WDT_CR); - /* write the second password magic with no config + /* + * write the second password magic with no config * this turns the watchdog off */ ltq_w32(LTQ_WDT_PW2, ltq_wdt_membase + LTQ_WDT_CR); @@ -184,7 +186,7 @@ static struct miscdevice ltq_wdt_miscdev = { .fops = <q_wdt_fops, }; -static int __init +static int __devinit ltq_wdt_probe(struct platform_device *pdev) { struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); @@ -194,28 +196,27 @@ ltq_wdt_probe(struct platform_device *pdev) dev_err(&pdev->dev, "cannot obtain I/O memory region"); return -ENOENT; } - res = devm_request_mem_region(&pdev->dev, res->start, - resource_size(res), dev_name(&pdev->dev)); - if (!res) { - dev_err(&pdev->dev, "cannot request I/O memory region"); - return -EBUSY; - } - ltq_wdt_membase = devm_ioremap_nocache(&pdev->dev, res->start, - resource_size(res)); + + ltq_wdt_membase = devm_request_and_ioremap(&pdev->dev, res); if (!ltq_wdt_membase) { dev_err(&pdev->dev, "cannot remap I/O memory region\n"); return -ENOMEM; } /* we do not need to enable the clock as it is always running */ - clk = clk_get(&pdev->dev, "io"); - WARN_ON(!clk); + clk = clk_get_io(); + if (IS_ERR(clk)) { + dev_err(&pdev->dev, "Failed to get clock\n"); + return -ENOENT; + } ltq_io_region_clk_rate = clk_get_rate(clk); clk_put(clk); + /* find out if the watchdog caused the last reboot */ if (ltq_reset_cause() == LTQ_RST_CAUSE_WDTRST) ltq_wdt_bootstatus = WDIOF_CARDRESET; + dev_info(&pdev->dev, "Init done\n"); return misc_register(<q_wdt_miscdev); } @@ -227,33 +228,26 @@ ltq_wdt_remove(struct platform_device *pdev) return 0; } +static const struct of_device_id ltq_wdt_match[] = { + { .compatible = "lantiq,wdt" }, + {}, +}; +MODULE_DEVICE_TABLE(of, ltq_wdt_match); static struct platform_driver ltq_wdt_driver = { + .probe = ltq_wdt_probe, .remove = __devexit_p(ltq_wdt_remove), .driver = { - .name = "ltq_wdt", + .name = "wdt", .owner = THIS_MODULE, + .of_match_table = ltq_wdt_match, }, }; -static int __init -init_ltq_wdt(void) -{ - return platform_driver_probe(<q_wdt_driver, ltq_wdt_probe); -} - -static void __exit -exit_ltq_wdt(void) -{ - return platform_driver_unregister(<q_wdt_driver); -} - -module_init(init_ltq_wdt); -module_exit(exit_ltq_wdt); +module_platform_driver(ltq_wdt_driver); module_param(nowayout, bool, 0); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"); - MODULE_AUTHOR("John Crispin "); MODULE_DESCRIPTION("Lantiq SoC Watchdog"); MODULE_LICENSE("GPL");