Re: [lm-sensors] [PATCH 1/2] applesmc: Use PnP rather thanhardcoding resources and devices

From: Guenter Roeck
Date: Thu Dec 16 2010 - 12:01:20 EST

On Thu, Dec 16, 2010 at 10:33:08AM -0500, Matthew Garrett wrote:
> The AppleSMC device is described in ACPI, including a list of its resources.
> We should use those rather than hardcoding the ports. A side-effect is that
> we can then remove the DMI matching, since there's a unique identifier to
> indicate that the machine has one of these devices.
>
> Signed-off-by: Matthew Garrett <mjg@xxxxxxxxxx>

Matthew,

I am having trouble applying this patch to my -next tree. The driver there
(and in the official -next tree) has subtle differences to your version.
What tree is your patch based on ? Can you rebase it to the -next tree and resubmit ?

Couple of comments below; not necessarily complete, since I can not apply the patch.
I hope Henrik can comment on the merits of the patch itself, ie if it is known to work
with all systems.

Thanks,
Guenter

> ---
> drivers/hwmon/applesmc.c | 185 +++++++++++++++++++++++-----------------------
> 1 files changed, 91 insertions(+), 94 deletions(-)
>
> diff --git a/drivers/hwmon/applesmc.c b/drivers/hwmon/applesmc.c
> index ee91d69..dbe3fa6 100644
> --- a/drivers/hwmon/applesmc.c
> +++ b/drivers/hwmon/applesmc.c
> @@ -30,7 +30,6 @@
> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>
> #include <linux/delay.h>
> -#include <linux/platform_device.h>
> #include <linux/input-polldev.h>
> #include <linux/kernel.h>
> #include <linux/slab.h>
> @@ -43,11 +42,13 @@
> #include <linux/leds.h>
> #include <linux/hwmon.h>
> #include <linux/workqueue.h>
> +#include <linux/slab.h>
> +#include <linux/pnp.h>
>
> /* data port used by Apple SMC */
> -#define APPLESMC_DATA_PORT 0x300
> +#define APPLESMC_DATA_PORT 0x0
> /* command/status port used by Apple SMC */
> -#define APPLESMC_CMD_PORT 0x304
> +#define APPLESMC_CMD_PORT 0x4
>
> #define APPLESMC_NR_PORTS 32 /* 0x300-0x31f */
>
> @@ -76,6 +77,8 @@
> #define MOTION_SENSOR_Z_KEY "MO_Z" /* r-o sp78 (2 bytes) */
> #define MOTION_SENSOR_KEY "MOCN" /* r/w ui16 */
>
> +#define NOTIFICATION_KEY "NTOK"
> +
> #define FANS_COUNT "FNum" /* r-o ui8 */
> #define FANS_MANUAL "FS! " /* r-w ui16 */
> #define FAN_ID_FMT "F%dID" /* r-o char[16] */
> @@ -103,6 +106,14 @@ static const char *const fan_speed_fmt[] = {
> #define to_index(attr) (to_sensor_dev_attr(attr)->index & 0xffff)
> #define to_option(attr) (to_sensor_dev_attr(attr)->index >> 16)
>
> +struct applesmc_pnp_device {
> + int iobase;
> + int iolen;
> +};
> +
> +struct pnp_dev *pdev;
> +struct applesmc_pnp_device *pnp_device;
> +
Please make those variables static.

> /* Dynamic device node attributes */
> struct applesmc_dev_attr {
> struct sensor_device_attribute sda; /* hwmon attributes */
> @@ -143,7 +154,6 @@ static struct applesmc_registers {
> } smcreg;
>
> static const int debug;
> -static struct platform_device *pdev;
> static s16 rest_x;
> static s16 rest_y;
> static u8 backlight_state[2];
> @@ -159,6 +169,16 @@ static unsigned int key_at_index;
>
> static struct workqueue_struct *applesmc_led_wq;
>
> +static u8 applesmc_read_reg(u8 reg)
> +{
> + return inb(pnp_device->iobase + reg);
> +}
> +
> +static void applesmc_write_reg(u8 val, u8 reg)
> +{
> + outb(val, pnp_device->iobase + reg);
> +}
> +
> /*
> * __wait_status - Wait up to 32ms for the status port to get a certain value
> * (masked with 0x0f), returning zero if the value is obtained. Callers must
> @@ -172,7 +192,8 @@ static int __wait_status(u8 val)
>
> for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
> udelay(us);
> - if ((inb(APPLESMC_CMD_PORT) & APPLESMC_STATUS_MASK) == val) {
> + if ((applesmc_read_reg(APPLESMC_CMD_PORT)
> + & APPLESMC_STATUS_MASK) == val) {
> return 0;
> }
> }
> @@ -189,9 +210,10 @@ static int send_command(u8 cmd)
> {
> int us;
> for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
> - outb(cmd, APPLESMC_CMD_PORT);
> + applesmc_write_reg(cmd, APPLESMC_CMD_PORT);
> udelay(us);
> - if ((inb(APPLESMC_CMD_PORT) & APPLESMC_STATUS_MASK) == 0x0c)
> + if ((applesmc_read_reg(APPLESMC_CMD_PORT)
> + & APPLESMC_STATUS_MASK) == 0x0c)
> return 0;
> }
> return -EIO;
> @@ -202,7 +224,7 @@ static int send_argument(const char *key)
> int i;
>
> for (i = 0; i < 4; i++) {
> - outb(key[i], APPLESMC_DATA_PORT);
> + applesmc_write_reg(key[i], APPLESMC_DATA_PORT);
> if (__wait_status(0x04))
> return -EIO;
> }
> @@ -218,14 +240,14 @@ static int read_smc(u8 cmd, const char *key, u8 *buffer, u8 len)
> return -EIO;
> }
>
> - outb(len, APPLESMC_DATA_PORT);
> + applesmc_write_reg(len, APPLESMC_DATA_PORT);
>
> for (i = 0; i < len; i++) {
> if (__wait_status(0x05)) {
> pr_warn("%s: read data fail\n", key);
> return -EIO;
> }
> - buffer[i] = inb(APPLESMC_DATA_PORT);
> + buffer[i] = applesmc_read_reg(APPLESMC_DATA_PORT);
> }
>
> return 0;
> @@ -240,14 +262,14 @@ static int write_smc(u8 cmd, const char *key, const u8 *buffer, u8 len)
> return -EIO;
> }
>
> - outb(len, APPLESMC_DATA_PORT);
> + applesmc_write_reg(len, APPLESMC_DATA_PORT);
>
> for (i = 0; i < len; i++) {
> if (__wait_status(0x04)) {
> pr_warn("%s: write data fail\n", key);
> return -EIO;
> }
> - outb(buffer[i], APPLESMC_DATA_PORT);
> + applesmc_write_reg(buffer[i], APPLESMC_DATA_PORT);
> }
>
> return 0;
> @@ -566,20 +588,6 @@ static void applesmc_destroy_smcreg(void)
> memset(&smcreg, 0, sizeof(smcreg));
> }
>
> -/* Device model stuff */
> -static int applesmc_probe(struct platform_device *dev)
> -{
> - int ret;
> -
> - ret = applesmc_init_smcreg();
> - if (ret)
> - return ret;
> -
> - applesmc_device_init();
> -
> - return 0;
> -}
> -
> /* Synchronize device with memorized backlight state */
> static int applesmc_pm_resume(struct device *dev)
> {
> @@ -600,15 +608,6 @@ static const struct dev_pm_ops applesmc_pm_ops = {
> .restore = applesmc_pm_restore,
> };
>
> -static struct platform_driver applesmc_driver = {
> - .probe = applesmc_probe,
> - .driver = {
> - .name = "applesmc",
> - .owner = THIS_MODULE,
> - .pm = &applesmc_pm_ops,
> - },
> -};
> -
> /*
> * applesmc_calibrate - Set our "resting" values. Callers must
> * hold applesmc_lock.
> @@ -1174,72 +1173,48 @@ static void applesmc_release_key_backlight(void)
> destroy_workqueue(applesmc_led_wq);
> }
>
> -static int applesmc_dmi_match(const struct dmi_system_id *id)
> +static int __devinit applesmc_pnp_probe(struct pnp_dev *dev,
> + const struct pnp_device_id *dev_id)
> {
> - return 1;
> -}
> + int ret;
> + struct resource *res;
> + struct applesmc_pnp_device *applesmc_pnp_device;
>
> -/* Note that DMI_MATCH(...,"MacBook") will match "MacBookPro1,1".
> - * So we need to put "Apple MacBook Pro" before "Apple MacBook". */
> -static __initdata struct dmi_system_id applesmc_whitelist[] = {
> - { applesmc_dmi_match, "Apple MacBook Air", {
> - DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
> - DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir") },
> - },
> - { applesmc_dmi_match, "Apple MacBook Pro", {
> - DMI_MATCH(DMI_BOARD_VENDOR,"Apple"),
> - DMI_MATCH(DMI_PRODUCT_NAME,"MacBookPro") },
> - },
> - { applesmc_dmi_match, "Apple MacBook", {
> - DMI_MATCH(DMI_BOARD_VENDOR,"Apple"),
> - DMI_MATCH(DMI_PRODUCT_NAME,"MacBook") },
> - },
> - { applesmc_dmi_match, "Apple Macmini", {
> - DMI_MATCH(DMI_BOARD_VENDOR,"Apple"),
> - DMI_MATCH(DMI_PRODUCT_NAME,"Macmini") },
> - },
> - { applesmc_dmi_match, "Apple MacPro", {
> - DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
> - DMI_MATCH(DMI_PRODUCT_NAME, "MacPro") },
> - },
> - { applesmc_dmi_match, "Apple iMac", {
> - DMI_MATCH(DMI_BOARD_VENDOR,"Apple"),
> - DMI_MATCH(DMI_PRODUCT_NAME,"iMac") },
> - },
> - { .ident = NULL }
> -};
> + pdev = dev;
>
> -static int __init applesmc_init(void)
> -{
> - int ret;
> + applesmc_pnp_device = kzalloc(sizeof(struct applesmc_pnp_device),
> + GFP_KERNEL);
>
> - if (!dmi_check_system(applesmc_whitelist)) {
> - pr_warn("supported laptop not found!\n");
> - ret = -ENODEV;
> + if (!applesmc_pnp_device) {
> + ret = -ENOMEM;
> goto out;
> }
>
> - if (!request_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS,
> - "applesmc")) {
> + pnp_device = applesmc_pnp_device;
> +
Just wondering ... applesmc_pnp_device doesn't seem to be necessary.
Why not just use the global variable directly if you have it anyway ?

> + pnp_set_drvdata(dev, applesmc_pnp_device);
> +

... but then since you assign it to drvdata, can you get rid of the global variable
and use pnp_get_drvdata() whereever it is needed instead ?

> + res = pnp_get_resource(dev, IORESOURCE_IO, 0);
> +
> + if (!res) {
> ret = -ENXIO;
> goto out;
> }
>
> - ret = platform_driver_register(&applesmc_driver);
> - if (ret)
> - goto out_region;
> + applesmc_pnp_device->iobase = res->start;
> + applesmc_pnp_device->iolen = res->end - res->start + 1;
>
> - pdev = platform_device_register_simple("applesmc", APPLESMC_DATA_PORT,
> - NULL, 0);
> - if (IS_ERR(pdev)) {
> - ret = PTR_ERR(pdev);
> - goto out_driver;
> + if (!request_region(pnp_device->iobase, pnp_device->iolen, "applesmc")) {

This line has more than 80 columns.

> + ret = -ENXIO;
> + goto out;
> }
>
> /* create register cache */
> ret = applesmc_init_smcreg();
> if (ret)
> - goto out_device;
> + goto out_region;
> +
> + applesmc_device_init();
>
> ret = applesmc_create_nodes(info_group, 1);
> if (ret)
> @@ -1287,19 +1262,17 @@ out_info:
> applesmc_destroy_nodes(info_group);
> out_smcreg:
> applesmc_destroy_smcreg();
> -out_device:
> - platform_device_unregister(pdev);
> -out_driver:
> - platform_driver_unregister(&applesmc_driver);
> out_region:
> - release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
> + release_region(pnp_device->iobase, pnp_device->iolen);

No kfree() of applesmc_pnp_device, so you are leaking memory here.

> out:
> pr_warn("driver init failed (ret=%d)!\n", ret);
> return ret;
> }
>
> -static void __exit applesmc_exit(void)
> +static void __devexit applesmc_pnp_remove(struct pnp_dev *dev)
> {
> + struct applesmc_pnp_device *applesmc_pnp_device = pnp_get_drvdata(dev);
> +

Why bother with this, as it is assigned to pnp_device ?

> hwmon_device_unregister(hwmon_dev);
> applesmc_release_key_backlight();
> applesmc_release_light_sensor();
> @@ -1308,9 +1281,33 @@ static void __exit applesmc_exit(void)
> applesmc_destroy_nodes(fan_group);
> applesmc_destroy_nodes(info_group);
> applesmc_destroy_smcreg();
> - platform_device_unregister(pdev);
> - platform_driver_unregister(&applesmc_driver);
> - release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
> + release_region(pnp_device->iobase, pnp_device->iolen);
> + kfree(applesmc_pnp_device);
> +}
> +
> +static const struct pnp_device_id applesmc_dev_table[] = {
> + {"APP0001", 0},
> + {"", 0},
> +};
> +
> +static struct pnp_driver applesmc_pnp_driver = {
> + .name = "Apple SMC",
> + .probe = applesmc_pnp_probe,
> + .remove = applesmc_pnp_remove,
> + .id_table = applesmc_dev_table,
> + .driver = {
> + .pm = &applesmc_pm_ops,
> + },
> +};
> +
> +static int __init applesmc_init(void)
> +{
> + return pnp_register_driver(&applesmc_pnp_driver);
> +}
> +
> +static void __exit applesmc_exit(void)
> +{
> + pnp_unregister_driver(&applesmc_pnp_driver);
> }
>
> module_init(applesmc_init);
> @@ -1319,4 +1316,4 @@ module_exit(applesmc_exit);
> MODULE_AUTHOR("Nicolas Boichat");
> MODULE_DESCRIPTION("Apple SMC");
> MODULE_LICENSE("GPL v2");
> -MODULE_DEVICE_TABLE(dmi, applesmc_whitelist);
> +MODULE_DEVICE_TABLE(pnp, applesmc_dev_table);
> --
> 1.7.3.3
>
>
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