From fc5462f8525b47fa219452289ecb22c921c16823 Mon Sep 17 00:00:00 2001 From: Azael Avalos Date: Wed, 22 Jul 2015 18:09:11 -0600 Subject: toshiba_acpi: Add /dev/toshiba_acpi device There were previous attempts to "merge" the toshiba SMM module to the toshiba_acpi one, they were trying to imitate what the old toshiba module does, however, some models (TOS1900 devices) come with a "crippled" implementation and do not provide all the "features" a "genuine" Toshiba BIOS does. This patch adds a new device called toshiba_acpi, which aim is to enable userspace to access the SMM on Toshiba laptops via ACPI calls. Creating a new convenience _IOWR command to access the SCI functions by opening/closing the SCI internally to avoid buggy BIOS, while at the same time providing backwards compatibility. Older programs (and new) who wish to access the SMM on newer models can do it by pointing their path to /dev/toshiba_acpi (instead of /dev/toshiba) as the toshiba.h header was modified to reflect these changes as well as adds all the toshiba_acpi paths and command, however, it is strongly recommended to use the new IOCTL for any SCI command to avoid any buggy BIOS. Signed-off-by: Azael Avalos Signed-off-by: Darren Hart --- drivers/platform/x86/toshiba_acpi.c | 91 +++++++++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) (limited to 'drivers') diff --git a/drivers/platform/x86/toshiba_acpi.c b/drivers/platform/x86/toshiba_acpi.c index c3a0c4d0c1dc..802577f43a23 100644 --- a/drivers/platform/x86/toshiba_acpi.c +++ b/drivers/platform/x86/toshiba_acpi.c @@ -50,6 +50,8 @@ #include #include #include +#include +#include #include MODULE_AUTHOR("John Belmonte"); @@ -170,6 +172,7 @@ struct toshiba_acpi_dev { struct led_classdev led_dev; struct led_classdev kbd_led; struct led_classdev eco_led; + struct miscdevice miscdev; int force_fan; int last_key_event; @@ -2239,6 +2242,81 @@ static struct attribute_group toshiba_attr_group = { .attrs = toshiba_attributes, }; +/* + * Misc device + */ +static int toshiba_acpi_smm_bridge(SMMRegisters *regs) +{ + u32 in[TCI_WORDS] = { regs->eax, regs->ebx, regs->ecx, + regs->edx, regs->esi, regs->edi }; + u32 out[TCI_WORDS]; + acpi_status status; + + status = tci_raw(toshiba_acpi, in, out); + if (ACPI_FAILURE(status)) { + pr_err("ACPI call to query SMM registers failed\n"); + return -EIO; + } + + /* Fillout the SMM struct with the TCI call results */ + regs->eax = out[0]; + regs->ebx = out[1]; + regs->ecx = out[2]; + regs->edx = out[3]; + regs->esi = out[4]; + regs->edi = out[5]; + + return 0; +} + +static long toshiba_acpi_ioctl(struct file *fp, unsigned int cmd, + unsigned long arg) +{ + SMMRegisters __user *argp = (SMMRegisters __user *)arg; + SMMRegisters regs; + int ret; + + if (!argp) + return -EINVAL; + + switch (cmd) { + case TOSH_SMM: + if (copy_from_user(®s, argp, sizeof(SMMRegisters))) + return -EFAULT; + ret = toshiba_acpi_smm_bridge(®s); + if (ret) + return ret; + if (copy_to_user(argp, ®s, sizeof(SMMRegisters))) + return -EFAULT; + break; + case TOSHIBA_ACPI_SCI: + if (copy_from_user(®s, argp, sizeof(SMMRegisters))) + return -EFAULT; + /* Ensure we are being called with a SCI_{GET, SET} register */ + if (regs.eax != SCI_GET && regs.eax != SCI_SET) + return -EINVAL; + if (!sci_open(toshiba_acpi)) + return -EIO; + ret = toshiba_acpi_smm_bridge(®s); + sci_close(toshiba_acpi); + if (ret) + return ret; + if (copy_to_user(argp, ®s, sizeof(SMMRegisters))) + return -EFAULT; + break; + default: + return -EINVAL; + } + + return 0; +} + +static const struct file_operations toshiba_acpi_fops = { + .owner = THIS_MODULE, + .unlocked_ioctl = toshiba_acpi_ioctl, + .llseek = noop_llseek, +}; + /* * Hotkeys */ @@ -2540,6 +2618,8 @@ static int toshiba_acpi_remove(struct acpi_device *acpi_dev) { struct toshiba_acpi_dev *dev = acpi_driver_data(acpi_dev); + misc_deregister(&dev->miscdev); + remove_toshiba_proc_entries(dev); if (dev->sysfs_created) @@ -2611,6 +2691,17 @@ static int toshiba_acpi_add(struct acpi_device *acpi_dev) return -ENOMEM; dev->acpi_dev = acpi_dev; dev->method_hci = hci_method; + dev->miscdev.minor = MISC_DYNAMIC_MINOR; + dev->miscdev.name = "toshiba_acpi"; + dev->miscdev.fops = &toshiba_acpi_fops; + + ret = misc_register(&dev->miscdev); + if (ret) { + pr_err("Failed to register miscdevice\n"); + kfree(dev); + return ret; + } + acpi_dev->driver_data = dev; dev_set_drvdata(&acpi_dev->dev, dev); -- cgit v1.2.3-58-ga151