From fa0bff02239abdad446effef22e5db281cf3d562 Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Wed, 16 Dec 2009 21:38:27 +0100 Subject: hwmon: (smsc47m1) Enable device if needed If the address is set but the device isn't enabled, attempt to enable it. If it won't work for any reason (resource conflict, no function enabled) the initial state is restored. The initial state is also restored on module unloading. Signed-off-by: Jean Delvare Tested-by: Sean Fidler --- drivers/hwmon/smsc47m1.c | 30 +++++++++++++++++++++++++++--- 1 file changed, 27 insertions(+), 3 deletions(-) (limited to 'drivers/hwmon/smsc47m1.c') diff --git a/drivers/hwmon/smsc47m1.c b/drivers/hwmon/smsc47m1.c index 92cca512b38..9ca97818bd4 100644 --- a/drivers/hwmon/smsc47m1.c +++ b/drivers/hwmon/smsc47m1.c @@ -136,6 +136,7 @@ struct smsc47m1_data { struct smsc47m1_sio_data { enum chips type; + u8 activate; /* Remember initial device state */ }; @@ -468,17 +469,38 @@ static int __init smsc47m1_find(unsigned short *addr, superio_select(); *addr = (superio_inb(SUPERIO_REG_BASE) << 8) | superio_inb(SUPERIO_REG_BASE + 1); - val = superio_inb(SUPERIO_REG_ACT); - if (*addr == 0 || (val & 0x01) == 0) { - pr_info(DRVNAME ": Device is disabled, will not use\n"); + if (*addr == 0) { + pr_info(DRVNAME ": Device address not set, will not use\n"); superio_exit(); return -ENODEV; } + /* Enable only if address is set (needed at least on the + * Compaq Presario S4000NX) */ + sio_data->activate = superio_inb(SUPERIO_REG_ACT); + if ((sio_data->activate & 0x01) == 0) { + pr_info(DRVNAME ": Enabling device\n"); + superio_outb(SUPERIO_REG_ACT, sio_data->activate | 0x01); + } + superio_exit(); return 0; } +/* Restore device to its initial state */ +static void __init smsc47m1_restore(const struct smsc47m1_sio_data *sio_data) +{ + if ((sio_data->activate & 0x01) == 0) { + superio_enter(); + superio_select(); + + pr_info(DRVNAME ": Disabling device\n"); + superio_outb(SUPERIO_REG_ACT, sio_data->activate); + + superio_exit(); + } +} + #define CHECK 1 #define REQUEST 2 #define RELEASE 3 @@ -856,6 +878,7 @@ static int __init sm_smsc47m1_init(void) exit_device: platform_device_unregister(pdev); + smsc47m1_restore(&sio_data); exit: return err; } @@ -863,6 +886,7 @@ exit: static void __exit sm_smsc47m1_exit(void) { platform_driver_unregister(&smsc47m1_driver); + smsc47m1_restore(pdev->dev.platform_data); platform_device_unregister(pdev); } -- cgit v1.2.3-70-g09d2