Re: [PATCH] Cleanup pc87413 watchdog driver to userequest_muxed_region for SuperIO area

From: Jonathan McDowell
Date: Sat Apr 30 2011 - 14:25:19 EST


I haven't seen any response to the below. Did I send it to the correct
places?

On Thu, Apr 14, 2011 at 12:02:38PM -0700, Jonathan McDowell wrote:
> Inspired by Nat Gurumoorthy's recent patches for cleaning up the it87
> drivers to use request_muxed_region for accessing the SuperIO area on
> these chips, and the fact I have a GPIO driver for the pc8741x basically
> ready for submission, here is a patch to cleanup the pc87413 watchdog
> driver to use request_muxed_region for accessing the SuperIO area.
>
> It also pulls out the details about the SWC IO area on initial driver
> load, and properly does a request_region for that area - there's no
> requirement to touch the SuperIO area after doing the initial watchdog
> enable and IO base retrieval.
>
> While I have hardware with a pc87413 on it it is not wired in a way that
> allows the watchdog to reboot the machine, so I have not been able to
> fully test these changes - I have checked that the driver correctly
> initialises itself still and requests the SWC io region ok.
>
> Signed-Off-By: Jonathan McDowell <noodles@xxxxxxxx>
>
> -------
> diff --git a/drivers/watchdog/pc87413_wdt.c b/drivers/watchdog/pc87413_wdt.c
> index b7c1390..e78d899 100644
> --- a/drivers/watchdog/pc87413_wdt.c
> +++ b/drivers/watchdog/pc87413_wdt.c
> @@ -56,6 +56,7 @@
> #define IO_DEFAULT 0x2E /* Address used on Portwell Boards */
>
> static int io = IO_DEFAULT;
> +static int swc_base_addr = -1;
>
> static int timeout = DEFAULT_TIMEOUT; /* timeout value */
> static unsigned long timer_enabled; /* is the timer enabled? */
> @@ -116,9 +117,8 @@ static inline void pc87413_enable_swc(void)
>
> /* Read SWC I/O base address */
>
> -static inline unsigned int pc87413_get_swc_base(void)
> +static void pc87413_get_swc_base_addr(void)
> {
> - unsigned int swc_base_addr = 0;
> unsigned char addr_l, addr_h = 0;
>
> /* Step 3: Read SWC I/O Base Address */
> @@ -136,12 +136,11 @@ static inline unsigned int pc87413_get_swc_base(void)
> "Read SWC I/O Base Address: low %d, high %d, res %d\n",
> addr_l, addr_h, swc_base_addr);
> #endif
> - return swc_base_addr;
> }
>
> /* Select Bank 3 of SWC */
>
> -static inline void pc87413_swc_bank3(unsigned int swc_base_addr)
> +static inline void pc87413_swc_bank3(void)
> {
> /* Step 4: Select Bank3 of SWC */
> outb_p(inb(swc_base_addr + 0x0f) | 0x03, swc_base_addr + 0x0f);
> @@ -152,8 +151,7 @@ static inline void pc87413_swc_bank3(unsigned int swc_base_addr)
>
> /* Set watchdog timeout to x minutes */
>
> -static inline void pc87413_programm_wdto(unsigned int swc_base_addr,
> - char pc87413_time)
> +static inline void pc87413_programm_wdto(char pc87413_time)
> {
> /* Step 5: Programm WDTO, Twd. */
> outb_p(pc87413_time, swc_base_addr + WDTO);
> @@ -164,7 +162,7 @@ static inline void pc87413_programm_wdto(unsigned int swc_base_addr,
>
> /* Enable WDEN */
>
> -static inline void pc87413_enable_wden(unsigned int swc_base_addr)
> +static inline void pc87413_enable_wden(void)
> {
> /* Step 6: Enable WDEN */
> outb_p(inb(swc_base_addr + WDCTL) | 0x01, swc_base_addr + WDCTL);
> @@ -174,7 +172,7 @@ static inline void pc87413_enable_wden(unsigned int swc_base_addr)
> }
>
> /* Enable SW_WD_TREN */
> -static inline void pc87413_enable_sw_wd_tren(unsigned int swc_base_addr)
> +static inline void pc87413_enable_sw_wd_tren(void)
> {
> /* Enable SW_WD_TREN */
> outb_p(inb(swc_base_addr + WDCFG) | 0x80, swc_base_addr + WDCFG);
> @@ -185,7 +183,7 @@ static inline void pc87413_enable_sw_wd_tren(unsigned int swc_base_addr)
>
> /* Disable SW_WD_TREN */
>
> -static inline void pc87413_disable_sw_wd_tren(unsigned int swc_base_addr)
> +static inline void pc87413_disable_sw_wd_tren(void)
> {
> /* Disable SW_WD_TREN */
> outb_p(inb(swc_base_addr + WDCFG) & 0x7f, swc_base_addr + WDCFG);
> @@ -196,7 +194,7 @@ static inline void pc87413_disable_sw_wd_tren(unsigned int swc_base_addr)
>
> /* Enable SW_WD_TRG */
>
> -static inline void pc87413_enable_sw_wd_trg(unsigned int swc_base_addr)
> +static inline void pc87413_enable_sw_wd_trg(void)
> {
> /* Enable SW_WD_TRG */
> outb_p(inb(swc_base_addr + WDCTL) | 0x80, swc_base_addr + WDCTL);
> @@ -207,7 +205,7 @@ static inline void pc87413_enable_sw_wd_trg(unsigned int swc_base_addr)
>
> /* Disable SW_WD_TRG */
>
> -static inline void pc87413_disable_sw_wd_trg(unsigned int swc_base_addr)
> +static inline void pc87413_disable_sw_wd_trg(void)
> {
> /* Disable SW_WD_TRG */
> outb_p(inb(swc_base_addr + WDCTL) & 0x7f, swc_base_addr + WDCTL);
> @@ -222,18 +220,13 @@ static inline void pc87413_disable_sw_wd_trg(unsigned int swc_base_addr)
>
> static void pc87413_enable(void)
> {
> - unsigned int swc_base_addr;
> -
> spin_lock(&io_lock);
>
> - pc87413_select_wdt_out();
> - pc87413_enable_swc();
> - swc_base_addr = pc87413_get_swc_base();
> - pc87413_swc_bank3(swc_base_addr);
> - pc87413_programm_wdto(swc_base_addr, timeout);
> - pc87413_enable_wden(swc_base_addr);
> - pc87413_enable_sw_wd_tren(swc_base_addr);
> - pc87413_enable_sw_wd_trg(swc_base_addr);
> + pc87413_swc_bank3();
> + pc87413_programm_wdto(timeout);
> + pc87413_enable_wden();
> + pc87413_enable_sw_wd_tren();
> + pc87413_enable_sw_wd_trg();
>
> spin_unlock(&io_lock);
> }
> @@ -242,17 +235,12 @@ static void pc87413_enable(void)
>
> static void pc87413_disable(void)
> {
> - unsigned int swc_base_addr;
> -
> spin_lock(&io_lock);
>
> - pc87413_select_wdt_out();
> - pc87413_enable_swc();
> - swc_base_addr = pc87413_get_swc_base();
> - pc87413_swc_bank3(swc_base_addr);
> - pc87413_disable_sw_wd_tren(swc_base_addr);
> - pc87413_disable_sw_wd_trg(swc_base_addr);
> - pc87413_programm_wdto(swc_base_addr, 0);
> + pc87413_swc_bank3();
> + pc87413_disable_sw_wd_tren();
> + pc87413_disable_sw_wd_trg();
> + pc87413_programm_wdto(0);
>
> spin_unlock(&io_lock);
> }
> @@ -261,20 +249,15 @@ static void pc87413_disable(void)
>
> static void pc87413_refresh(void)
> {
> - unsigned int swc_base_addr;
> -
> spin_lock(&io_lock);
>
> - pc87413_select_wdt_out();
> - pc87413_enable_swc();
> - swc_base_addr = pc87413_get_swc_base();
> - pc87413_swc_bank3(swc_base_addr);
> - pc87413_disable_sw_wd_tren(swc_base_addr);
> - pc87413_disable_sw_wd_trg(swc_base_addr);
> - pc87413_programm_wdto(swc_base_addr, timeout);
> - pc87413_enable_wden(swc_base_addr);
> - pc87413_enable_sw_wd_tren(swc_base_addr);
> - pc87413_enable_sw_wd_trg(swc_base_addr);
> + pc87413_swc_bank3();
> + pc87413_disable_sw_wd_tren();
> + pc87413_disable_sw_wd_trg();
> + pc87413_programm_wdto(timeout);
> + pc87413_enable_wden();
> + pc87413_enable_sw_wd_tren();
> + pc87413_enable_sw_wd_trg();
>
> spin_unlock(&io_lock);
> }
> @@ -528,7 +511,8 @@ static int __init pc87413_init(void)
> printk(KERN_INFO PFX "Version " VERSION " at io 0x%X\n",
> WDT_INDEX_IO_PORT);
>
> - /* request_region(io, 2, "pc87413"); */
> + if (!request_muxed_region(io, 2, MODNAME))
> + return -EBUSY;
>
> ret = register_reboot_notifier(&pc87413_notifier);
> if (ret != 0) {
> @@ -541,12 +525,32 @@ static int __init pc87413_init(void)
> printk(KERN_ERR PFX
> "cannot register miscdev on minor=%d (err=%d)\n",
> WATCHDOG_MINOR, ret);
> - unregister_reboot_notifier(&pc87413_notifier);
> - return ret;
> + goto reboot_unreg;
> }
> printk(KERN_INFO PFX "initialized. timeout=%d min \n", timeout);
> +
> + pc87413_select_wdt_out();
> + pc87413_enable_swc();
> + pc87413_get_swc_base_addr();
> +
> + if (!request_region(swc_base_addr, 0x20, MODNAME)) {
> + printk(KERN_ERR PFX
> + "cannot request SWC region at 0x%x\n", swc_base_addr);
> + ret = -EBUSY;
> + goto misc_unreg;
> + }
> +
> pc87413_enable();
> +
> + release_region(io, 2);
> return 0;
> +
> +misc_unreg:
> + misc_deregister(&pc87413_miscdev);
> +reboot_unreg:
> + unregister_reboot_notifier(&pc87413_notifier);
> + release_region(io, 2);
> + return ret;
> }
>
> /**
> @@ -569,7 +573,7 @@ static void __exit pc87413_exit(void)
>
> misc_deregister(&pc87413_miscdev);
> unregister_reboot_notifier(&pc87413_notifier);
> - /* release_region(io, 2); */
> + release_region(swc_base_addr, 0x20);
>
> printk(KERN_INFO MODNAME " watchdog component driver removed.\n");
> }
>
> -------

J.

--
/-\ | Do you believe in happy endings?
|@/ Debian GNU/Linux Developer |
\- |
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/