On Tue, Oct 20, 2020 at 08:21:11AM +0200, Ahmad Fatoum wrote:
> Driver so far wasn't ported to the driver model and set up its
> miscdevice out of the init after probing the I/O ports for a watchdog
> with correct vendor and device revision.
>
> Keep the device detection part at init time, but move watchdog setup
> to a platform driver probe function.
>
> While at it, refactor some of the driver code we have to now touch
> anyway:
>
> - platform_device_id is used instead of the two big switches mapping
> hardware ID to an enum and then mapping it to a pinconf function
> - we rename f71808e_ and watchdog_data to fintek_wdt, to avoid mix up
> of the generic parts up with the device specific parts
>
> Suggested-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
Sorry, I just found this. Sorry, it got lost.
The changes you are making here go way beyond a conversion to a platform
driver. I am not necessarily opposed to the changes, but they should be
split into multiple patches to simlify (and to a large degree enable)
a meaningful review. More comments inline.
> ---
> drivers/watchdog/f71808e_wdt.c | 377 +++++++++++++++++++--------------
> 1 file changed, 215 insertions(+), 162 deletions(-)
>
> diff --git a/drivers/watchdog/f71808e_wdt.c b/drivers/watchdog/f71808e_wdt.c
> index f60beec1bbae..4ff7a2509125 100644
> --- a/drivers/watchdog/f71808e_wdt.c
> +++ b/drivers/watchdog/f71808e_wdt.c
> @@ -9,12 +9,15 @@
> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>
> #include <linux/err.h>
> +#include <linux/slab.h>
> #include <linux/fs.h>
> #include <linux/init.h>
> #include <linux/io.h>
> #include <linux/ioport.h>
> #include <linux/miscdevice.h>
> #include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/mod_devicetable.h>
> #include <linux/mutex.h>
> #include <linux/notifier.h>
> #include <linux/reboot.h>
> @@ -110,22 +113,6 @@ module_param(start_withtimeout, uint, 0);
> MODULE_PARM_DESC(start_withtimeout, "Start watchdog timer on module load with"
> " given initial timeout. Zero (default) disables this feature.");
>
> -enum chips { f71808fg, f71858fg, f71862fg, f71868, f71869, f71882fg, f71889fg,
> - f81803, f81865, f81866};
> -
> -static const char *f71808e_names[] = {
> - "f71808fg",
> - "f71858fg",
> - "f71862fg",
> - "f71868",
> - "f71869",
> - "f71882fg",
> - "f71889fg",
> - "f81803",
> - "f81865",
> - "f81866",
> -};
> -
> /* Super-I/O Function prototypes */
> static inline int superio_inb(int base, int reg);
> static inline int superio_inw(int base, int reg);
> @@ -136,9 +123,17 @@ static inline int superio_enter(int base);
> static inline void superio_select(int base, int ld);
> static inline void superio_exit(int base);
>
> -struct watchdog_data {
> +struct fintek_wdt;
> +
> +struct fintek_wdt_variant {
> + u16 id;
> + void (*pinconf)(struct fintek_wdt *wd);
> + const char *identity_override;
> +};
> +
> +struct fintek_wdt {
> unsigned short sioaddr;
> - enum chips type;
> + const struct fintek_wdt_variant *variant;
I'd rather have this all in here. Just add
void (*pinconf)(struct fintek_wdt *wd);
and assign it in the probe function, or call it
from an array indexed with type.
This change is also independent of the conversion to a platform
driver and should be done in a separate patch.
> unsigned long opened;
> struct mutex lock;
> char expect_close;
> @@ -152,10 +147,15 @@ struct watchdog_data {
> char caused_reboot; /* last reboot was by the watchdog */
> };
>
> -static struct watchdog_data watchdog = {
> +static struct fintek_wdt watchdog = {
> .lock = __MUTEX_INITIALIZER(watchdog.lock),
> };
>
> +static inline bool has_f81865_wdo_conf(struct fintek_wdt *wd)
> +{
> + return wd->variant->id == SIO_F81865_ID || wd->variant->id == SIO_F81866_ID;
> +}
> +
This change is independent of the conversion to a platform driver
and should be a separate patch.
> /* Super I/O functions */
> static inline int superio_inb(int base, int reg)
> {
> @@ -247,7 +247,7 @@ static int watchdog_set_pulse_width(unsigned int pw)
> int err = 0;
> unsigned int t1 = 25, t2 = 125, t3 = 5000;
>
> - if (watchdog.type == f71868) {
> + if (watchdog.variant->id == SIO_F71868_ID) {
I am not sure if dropping watchdog.type and replacing it with SIO_F71868_ID
is a good idea. In the current code, there is no 1:1 match of those,
specifically for SIO_F71869_ID/SIO_F71869A_ID. Deviating from that only
complicates the code.
> t1 = 30;
> t2 = 150;
> t3 = 6000;
> @@ -309,7 +309,6 @@ static int watchdog_keepalive(void)
> static int watchdog_start(void)
> {
> int err;
> - u8 tmp;
>
> /* Make sure we don't die as soon as the watchdog is enabled below */
> err = watchdog_keepalive();
> @@ -323,81 +322,12 @@ static int watchdog_start(void)
> superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
>
> /* Watchdog pin configuration */
> - switch (watchdog.type) {
> - case f71808fg:
> - /* Set pin 21 to GPIO23/WDTRST#, then to WDTRST# */
> - superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT2, 3);
> - superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 3);
> - break;
> -
> - case f71862fg:
> - if (f71862fg_pin == 63) {
> - /* SPI must be disabled first to use this pin! */
> - superio_clear_bit(watchdog.sioaddr, SIO_REG_ROM_ADDR_SEL, 6);
> - superio_set_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 4);
> - } else if (f71862fg_pin == 56) {
> - superio_set_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 1);
> - }
> - break;
> -
> - case f71868:
> - case f71869:
> - /* GPIO14 --> WDTRST# */
> - superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 4);
> - break;
> -
> - case f71882fg:
> - /* Set pin 56 to WDTRST# */
> - superio_set_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 1);
> - break;
> -
> - case f71889fg:
> - /* set pin 40 to WDTRST# */
> - superio_outb(watchdog.sioaddr, SIO_REG_MFUNCT3,
> - superio_inb(watchdog.sioaddr, SIO_REG_MFUNCT3) & 0xcf);
> - break;
> -
> - case f81803:
> - /* Enable TSI Level register bank */
> - superio_clear_bit(watchdog.sioaddr, SIO_REG_CLOCK_SEL, 3);
> - /* Set pin 27 to WDTRST# */
> - superio_outb(watchdog.sioaddr, SIO_REG_TSI_LEVEL_SEL, 0x5f &
> - superio_inb(watchdog.sioaddr, SIO_REG_TSI_LEVEL_SEL));
> - break;
> -
> - case f81865:
> - /* Set pin 70 to WDTRST# */
> - superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 5);
> - break;
> -
> - case f81866:
> - /*
> - * GPIO1 Control Register when 27h BIT3:2 = 01 & BIT0 = 0.
> - * The PIN 70(GPIO15/WDTRST) is controlled by 2Ch:
> - * BIT5: 0 -> WDTRST#
> - * 1 -> GPIO15
> - */
> - tmp = superio_inb(watchdog.sioaddr, SIO_F81866_REG_PORT_SEL);
> - tmp &= ~(BIT(3) | BIT(0));
> - tmp |= BIT(2);
> - superio_outb(watchdog.sioaddr, SIO_F81866_REG_PORT_SEL, tmp);
> -
> - superio_clear_bit(watchdog.sioaddr, SIO_F81866_REG_GPIO1, 5);
> - break;
> -
> - default:
> - /*
> - * 'default' label to shut up the compiler and catch
> - * programmer errors
> - */
> - err = -ENODEV;
> - goto exit_superio;
> - }
> + watchdog.variant->pinconf(&watchdog);
>
> superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
> superio_set_bit(watchdog.sioaddr, SIO_REG_ENABLE, 0);
>
> - if (watchdog.type == f81865 || watchdog.type == f81866)
> + if (has_f81865_wdo_conf(&watchdog))
> superio_set_bit(watchdog.sioaddr, F81865_REG_WDO_CONF,
> F81865_FLAG_WDOUT_EN);
> else
> @@ -425,7 +355,6 @@ static int watchdog_start(void)
> F71808FG_FLAG_WD_PULSE);
> }
>
> -exit_superio:
> superio_exit(watchdog.sioaddr);
> exit_unlock:
> mutex_unlock(&watchdog.lock);
> @@ -665,21 +594,39 @@ static struct notifier_block watchdog_notifier = {
> .notifier_call = watchdog_notify_sys,
> };
>
> -static int __init watchdog_init(int sioaddr)
> +static int fintek_wdt_probe(struct platform_device *pdev)
> {
> + const struct platform_device_id *id;
> + unsigned short sioaddr;
> + struct resource *res;
> int wdt_conf, err = 0;
> + const char *identity;
> +
> + if (watchdog_miscdev.parent)
> + return -EBUSY;
> +
> + watchdog_miscdev.parent = &pdev->dev;
> +
> + res = platform_get_resource(pdev, IORESOURCE_IO, 0);
> + if (!res)
> + return -ENXIO;
> +
> + id = platform_get_device_id(pdev);
> + watchdog.variant = (void *)id->driver_data;
> + if (!watchdog.variant)
> + return -ENODEV;
>
> /* No need to lock watchdog.lock here because no entry points
> * into the module have been registered yet.
> */
> - watchdog.sioaddr = sioaddr;
> + watchdog.sioaddr = res->start;
> watchdog.ident.options = WDIOF_MAGICCLOSE
> | WDIOF_KEEPALIVEPING
> | WDIOF_CARDRESET;
>
> - snprintf(watchdog.ident.identity,
> - sizeof(watchdog.ident.identity), "%s watchdog",
> - f71808e_names[watchdog.type]);
> + identity = watchdog.variant->identity_override ?: id->name;
> +
> + memcpy(watchdog.ident.identity, identity, sizeof(watchdog.ident.identity));
>
> err = superio_enter(sioaddr);
> if (err)
> @@ -772,73 +719,176 @@ static int __init watchdog_init(int sioaddr)
> return err;
> }
>
> -static int __init f71808e_find(int sioaddr)
> +static void f71808fg_pinconf(struct fintek_wdt *wd)
> {
> + /* Set pin 21 to GPIO23/WDTRST#, then to WDTRST# */
> + superio_clear_bit(wd->sioaddr, SIO_REG_MFUNCT2, 3);
> + superio_clear_bit(wd->sioaddr, SIO_REG_MFUNCT3, 3);
> +}
> +
> +static void f71862fg_pinconf(struct fintek_wdt *wd)
> +{
> + if (f71862fg_pin == 63) {
> + /* SPI must be disabled first to use this pin! */
> + superio_clear_bit(wd->sioaddr, SIO_REG_ROM_ADDR_SEL, 6);
> + superio_set_bit(wd->sioaddr, SIO_REG_MFUNCT3, 4);
> + } else if (f71862fg_pin == 56) {
> + superio_set_bit(wd->sioaddr, SIO_REG_MFUNCT1, 1);
> + }
> +}
> +
> +static void f71868_pinconf(struct fintek_wdt *wd)
> +{
> + /* GPIO14 --> WDTRST# */
> + superio_clear_bit(wd->sioaddr, SIO_REG_MFUNCT1, 4);
> +}
> +
> +static void f71882fg_pinconf(struct fintek_wdt *wd)
> +{
> + /* Set pin 56 to WDTRST# */
> + superio_set_bit(wd->sioaddr, SIO_REG_MFUNCT1, 1);
> +}
> +
> +static void f71889fg_pinconf(struct fintek_wdt *wd)
> +{
> + /* set pin 40 to WDTRST# */
> + superio_outb(wd->sioaddr, SIO_REG_MFUNCT3,
> + superio_inb(wd->sioaddr, SIO_REG_MFUNCT3) & 0xcf);
> +}
> +
> +static void f81803_pinconf(struct fintek_wdt *wd)
> +{
> + /* Enable TSI Level register bank */
> + superio_clear_bit(wd->sioaddr, SIO_REG_CLOCK_SEL, 3);
> + /* Set pin 27 to WDTRST# */
> + superio_outb(wd->sioaddr, SIO_REG_TSI_LEVEL_SEL, 0x5f &
> + superio_inb(wd->sioaddr, SIO_REG_TSI_LEVEL_SEL));
> +}
> +
> +static void f81865_pinconf(struct fintek_wdt *wd)
> +{
> + /* Set pin 70 to WDTRST# */
> + superio_clear_bit(wd->sioaddr, SIO_REG_MFUNCT3, 5);
> +}
> +
> +static void f81866_pinconf(struct fintek_wdt *wd)
> +{
> + u8 tmp;
> + /*
> + * GPIO1 Control Register when 27h BIT3:2 = 01 & BIT0 = 0.
> + * The PIN 70(GPIO15/WDTRST) is controlled by 2Ch:
> + * BIT5: 0 -> WDTRST#
> + * 1 -> GPIO15
> + */
> + tmp = superio_inb(wd->sioaddr, SIO_F81866_REG_PORT_SEL);
> + tmp &= ~(BIT(3) | BIT(0));
> + tmp |= BIT(2);
> + superio_outb(wd->sioaddr, SIO_F81866_REG_PORT_SEL, tmp);
> +
> + superio_clear_bit(wd->sioaddr, SIO_F81866_REG_GPIO1, 5);
> +}
> +
> +#define FINTEK_DRV_DATA(...) \
> + (kernel_ulong_t)(&(struct fintek_wdt_variant) { __VA_ARGS__ })
> +
> +/*
> + * Array is used by both platform bus to map name to driver data and by
> + * init below to map id in driver_data to name for device creation.
> + */
> +static const struct platform_device_id fintek_wdt_id_table[] = {
> + { "f71808fg watchdog", FINTEK_DRV_DATA(SIO_F71808_ID, f71808fg_pinconf) },
> + { "f71862fg watchdog", FINTEK_DRV_DATA(SIO_F71862_ID, f71862fg_pinconf) },
> + { "f71868 watchdog", FINTEK_DRV_DATA(SIO_F71868_ID, f71868_pinconf) },
> + { "f71869 watchdog", FINTEK_DRV_DATA(SIO_F71869_ID, f71868_pinconf) },
> + /* For backwards-compatibility, we define a different watchdog identity name */
> + { "f71869a watchdog", FINTEK_DRV_DATA(SIO_F71869A_ID, f71868_pinconf,
> + .identity_override = "f71869 watchdog") },
I don't think .identity_override adds real value.
> + { "f71882fg watchdog", FINTEK_DRV_DATA(SIO_F71882_ID, f71882fg_pinconf) },
> + { "f71889fg watchdog", FINTEK_DRV_DATA(SIO_F71889_ID, f71889fg_pinconf) },
> + { "f81803 watchdog", FINTEK_DRV_DATA(SIO_F81803_ID, f81803_pinconf) },
> + { "f81865 watchdog", FINTEK_DRV_DATA(SIO_F81865_ID, f81865_pinconf) },
> + { "f81866 watchdog", FINTEK_DRV_DATA(SIO_F81866_ID, f81866_pinconf) },
I am not entirely sure I understand exactly what the macro does, and checkpatch
doesn't like it either.
Anyway, I don't think this complexity is necessary. Other similar drivers add
device information as platform driver data (using platform_device_add_data)
and get it using dev_get_platdata(). That would be much simpler and more
straightforward.
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(platform, fintek_wdt_id_table);
> +
> +/* Confirmed (by datasheet) not to have a watchdog.
> + * We list this here anyway to maintain backwards-compatibility in not warning about them
> + */
> +static const u16 fintek_no_wdt_table[] = { SIO_F71858_ID, 0 };
> +
> +static int fintek_wdt_remove(struct platform_device *pdev)
> +{
> + if (watchdog_is_running()) {
> + pr_warn("Watchdog timer still running, stopping it\n");
> + watchdog_stop();
> + }
> + misc_deregister(&watchdog_miscdev);
> + unregister_reboot_notifier(&watchdog_notifier);
> + return 0;
> +}
> +
> +static struct platform_driver fintek_wdt_driver = {
> + .probe = fintek_wdt_probe,
> + .remove = fintek_wdt_remove,
> + .id_table = fintek_wdt_id_table,
> + .driver = {
> + .name = DRVNAME,
> + },
> +};
> +
> +static struct platform_device *fintek_wdt_pdev;
> +
> +static __init const char *fintek_wdt_find(int sioaddr)
> +{
> + const char *name = ERR_PTR(-ENODEV);
> + const struct platform_device_id *id;
> + struct fintek_wdt_variant *variant;
> u16 devid;
> - int err = superio_enter(sioaddr);
> + const u16 *pdevid;
> + int err;
> +
> + err = superio_enter(sioaddr);
> if (err)
> - return err;
> + return ERR_PTR(err);
>
> devid = superio_inw(sioaddr, SIO_REG_MANID);
> if (devid != SIO_FINTEK_ID) {
> pr_debug("Not a Fintek device\n");
> - err = -ENODEV;
> - goto exit;
> + goto out;
> }
>
> devid = force_id ? force_id : superio_inw(sioaddr, SIO_REG_DEVID);
> - switch (devid) {
> - case SIO_F71808_ID:
> - watchdog.type = f71808fg;
> - break;
> - case SIO_F71862_ID:
> - watchdog.type = f71862fg;
> - break;
> - case SIO_F71868_ID:
> - watchdog.type = f71868;
> - break;
> - case SIO_F71869_ID:
> - case SIO_F71869A_ID:
> - watchdog.type = f71869;
> - break;
> - case SIO_F71882_ID:
> - watchdog.type = f71882fg;
> - break;
> - case SIO_F71889_ID:
> - watchdog.type = f71889fg;
> - break;
> - case SIO_F71858_ID:
> - /* Confirmed (by datasheet) not to have a watchdog. */
> - err = -ENODEV;
> - goto exit;
> - case SIO_F81803_ID:
> - watchdog.type = f81803;
> - break;
> - case SIO_F81865_ID:
> - watchdog.type = f81865;
> - break;
> - case SIO_F81866_ID:
> - watchdog.type = f81866;
> - break;
> - default:
> - pr_info("Unrecognized Fintek device: %04x\n",
> - (unsigned int)devid);
> - err = -ENODEV;
> - goto exit;
> + for (id = fintek_wdt_id_table; id->driver_data; id++) {
> + variant = (void *)id->driver_data;
> + if (variant->id == devid) {
> + name = id->name;
> + pr_info("Found %s chip, revision %d\n",
> + name, superio_inb(sioaddr, SIO_REG_DEVREV));
> + goto out;
> + }
> + }
> +
> + for (pdevid = fintek_no_wdt_table; *pdevid; pdevid++) {
> + if (*pdevid == devid)
> + goto out;
I'd rather keep the old code here. I don't see a substantial benefit in
its replacement.
> }
>
> - pr_info("Found %s watchdog chip, revision %d\n",
> - f71808e_names[watchdog.type],
> - (int)superio_inb(sioaddr, SIO_REG_DEVREV));
> -exit:
> + pr_info("Unrecognized Fintek device: %04x\n", devid);
> +out:
> superio_exit(sioaddr);
> - return err;
> + return name;
> }
>
> -static int __init f71808e_init(void)
> +static struct resource wdt_res = {
> + .name = "superio port",
> + .flags = IORESOURCE_IO,
> +};
> +
> +static int __init fintek_wdt_init(void)
> {
> - static const unsigned short addrs[] = { 0x2e, 0x4e };
> - int err = -ENODEV;
> + unsigned short addrs[] = { 0x2e, 0x4e };
Why drop the static here ? It won't change.
> + const char *wdt_name;
> int i;
>
> if (f71862fg_pin != 63 && f71862fg_pin != 56) {
> @@ -846,30 +896,33 @@ static int __init f71808e_init(void)
> return -EINVAL;
> }
>
> + platform_driver_register(&fintek_wdt_driver);
> +
The driver should only be registered if a watchdog device is found.
> for (i = 0; i < ARRAY_SIZE(addrs); i++) {
> - err = f71808e_find(addrs[i]);
> - if (err == 0)
> + wdt_name = fintek_wdt_find(addrs[i]);
> + if (!IS_ERR(wdt_name))
> break;
> }
> +
> if (i == ARRAY_SIZE(addrs))
> - return err;
> + return PTR_ERR(wdt_name);
> +
> + wdt_res.start = addrs[i];
> + wdt_res.end = wdt_res.start + 1;
>
> - return watchdog_init(addrs[i]);
> + fintek_wdt_pdev = platform_device_register_simple(wdt_name, -1, &wdt_res, 1);
> + return PTR_ERR_OR_ZERO(fintek_wdt_pdev);
> }
>
> -static void __exit f71808e_exit(void)
> +static void __exit fintek_wdt_exit(void)
> {
> - if (watchdog_is_running()) {
> - pr_warn("Watchdog timer still running, stopping it\n");
> - watchdog_stop();
> - }
> - misc_deregister(&watchdog_miscdev);
> - unregister_reboot_notifier(&watchdog_notifier);
> + platform_device_unregister(fintek_wdt_pdev);
> + platform_driver_unregister(&fintek_wdt_driver);
> }
>
> MODULE_DESCRIPTION("F71808E Watchdog Driver");
> MODULE_AUTHOR("Giel van Schijndel <me@xxxxxxxxx>");
> MODULE_LICENSE("GPL");
>
> -module_init(f71808e_init);
> -module_exit(f71808e_exit);
> +module_init(fintek_wdt_init);
> +module_exit(fintek_wdt_exit);
