On Fri, Jul 3, 2020 at 4:24 AM Mark Pearson <markpearson@xxxxxxxxxx> wrote: > > Newer Lenovo Thinkpad platforms have support to identify whether the > system is on-lap or not using an ACPI DYTC event from the firmware. > > This patch provides the ability to retrieve the current mode via sysfs > entrypoints and will be used by userspace for thermal mode and WWAN > functionality Hans, do you think it's good to have custom ABI for this? I think you may be know better what types of ABI we already have for such thing. > Co-developed-by: Nitin Joshi <njoshi1@xxxxxxxxxx> > Signed-off-by: Nitin Joshi <njoshi1@xxxxxxxxxx> > Reviewed-by: Sugumaran <slacshiminar@xxxxxxxxxx> > Reviewed-by: Bastien Nocera <bnocera@xxxxxxxxxx> > Signed-off-by: Mark Pearson <markpearson@xxxxxxxxxx> > --- > Changes in v5: > - Updated with review changes from Andy Shevchenko > - Added ABI information to thinkpad-acpi.rst > - improved error handling and parameter passing as recommended > - code cleanup as recommended > - added review tag from bnocera > Changes in v4: > - Correct hotkey event comment as we're handling event > - Remove unnecessary check in dytc_lapmode_refresh > Changes in v3: > - Fixed inaccurate comments > - Used BIT macro to check lapmode bit setting as recommended and update > define name > - Check for new_state == dytc_lapmode in dytc_lapmode_refresh > Changes in v2: > - cleaned up initialisation sequence to be cleaner and avoid spamming > platforms that don't have DYTC with warning message. Tested on P52 > - Adding platform-driver-x86 mailing list for review as requested > > .../admin-guide/laptops/thinkpad-acpi.rst | 15 +++ > drivers/platform/x86/thinkpad_acpi.c | 111 +++++++++++++++++- > 2 files changed, 124 insertions(+), 2 deletions(-) > > diff --git a/Documentation/admin-guide/laptops/thinkpad-acpi.rst b/Documentation/admin-guide/laptops/thinkpad-acpi.rst > index 822907dcc845..99066aa8d97b 100644 > --- a/Documentation/admin-guide/laptops/thinkpad-acpi.rst > +++ b/Documentation/admin-guide/laptops/thinkpad-acpi.rst > @@ -50,6 +50,7 @@ detailed description): > - WAN enable and disable > - UWB enable and disable > - LCD Shadow (PrivacyGuard) enable and disable > + - Lap mode sensor > > A compatibility table by model and feature is maintained on the web > site, http://ibm-acpi.sf.net/. I appreciate any success or failure > @@ -1432,6 +1433,20 @@ The first command ensures the best viewing angle and the latter one turns > on the feature, restricting the viewing angles. > > > +DYTC Lapmode sensor > +------------------ > + > +sysfs: dytc_lapmode > + > +Newer thinkpads and mobile workstations have the ability to determine if > +the device is in deskmode or lapmode. This feature is used by user space > +to decide if WWAN transmission can be increased to maximum power and is > +also useful for understanding the different thermal modes available as > +they differ between desk and lap mode. > + > +The property is read-only. If the platform doesn't have support the sysfs > +class is not created. > + > EXPERIMENTAL: UWB > ----------------- > > diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c > index ff7f0a4f2475..037eb77414f9 100644 > --- a/drivers/platform/x86/thinkpad_acpi.c > +++ b/drivers/platform/x86/thinkpad_acpi.c > @@ -4022,8 +4022,8 @@ static bool hotkey_notify_6xxx(const u32 hkey, > return true; > case TP_HKEY_EV_THM_CSM_COMPLETED: > pr_debug("EC reports: Thermal Control Command set completed (DYTC)\n"); > - /* recommended action: do nothing, we don't have > - * Lenovo ATM information */ > + /* Thermal event - pass on to event handler */ > + tpacpi_driver_event(hkey); > return true; > case TP_HKEY_EV_THM_TRANSFM_CHANGED: > pr_debug("EC reports: Thermal Transformation changed (GMTS)\n"); > @@ -9795,6 +9795,105 @@ static struct ibm_struct lcdshadow_driver_data = { > .write = lcdshadow_write, > }; > > +/************************************************************************* > + * DYTC subdriver, for the Lenovo lapmode feature > + */ > + > +#define DYTC_CMD_GET 2 /* To get current IC function and mode */ > +#define DYTC_GET_LAPMODE_BIT 17 /* Set when in lapmode */ > + > +static bool dytc_lapmode; > + > +static void dytc_lapmode_notify_change(void) > +{ > + sysfs_notify(&tpacpi_pdev->dev.kobj, NULL, "dytc_lapmode"); > +} > + > +static int dytc_command(int command, int *output) > +{ > + acpi_handle dytc_handle; > + > + if (ACPI_FAILURE(acpi_get_handle(hkey_handle, "DYTC", &dytc_handle))) { > + /* Platform doesn't support DYTC */ > + return -ENODEV; > + } > + if (!acpi_evalf(dytc_handle, output, NULL, "dd", command)) > + return -EIO; > + return 0; > +} > + > +static int dytc_lapmode_get(bool *state) > +{ > + int output, err; > + > + err = dytc_command(DYTC_CMD_GET, &output); > + if (err) > + return err; > + *state = output & BIT(DYTC_GET_LAPMODE_BIT) ? true : false; > + return 0; > +} > + > +static void dytc_lapmode_refresh(void) > +{ > + bool new_state; > + int err; > + > + err = dytc_lapmode_get(&new_state); > + if (err || (new_state == dytc_lapmode)) > + return; > + > + dytc_lapmode = new_state; > + dytc_lapmode_notify_change(); > +} > + > +/* sysfs lapmode entry */ > +static ssize_t dytc_lapmode_show(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + return snprintf(buf, PAGE_SIZE, "%d\n", dytc_lapmode); > +} > + > +static DEVICE_ATTR_RO(dytc_lapmode); > + > +static struct attribute *dytc_attributes[] = { > + &dev_attr_dytc_lapmode.attr, > + NULL, > +}; > + > +static const struct attribute_group dytc_attr_group = { > + .attrs = dytc_attributes, > +}; > + > +static int tpacpi_dytc_init(struct ibm_init_struct *iibm) > +{ > + int err; > + > + err = dytc_lapmode_get(&dytc_lapmode); > + /* If support isn't available (ENODEV) then don't return an error > + * but just don't create the sysfs group > + */ > + if (err == -ENODEV) > + return 0; > + /* For all other errors we can flag the failure */ > + if (err) > + return err; > + > + /* Platform supports this feature - create the group */ > + err = sysfs_create_group(&tpacpi_pdev->dev.kobj, &dytc_attr_group); > + return err; > +} > + > +static void dytc_exit(void) > +{ > + sysfs_remove_group(&tpacpi_pdev->dev.kobj, &dytc_attr_group); > +} > + > +static struct ibm_struct dytc_driver_data = { > + .name = "dytc", > + .exit = dytc_exit, > +}; > + > /**************************************************************************** > **************************************************************************** > * > @@ -9842,6 +9941,10 @@ static void tpacpi_driver_event(const unsigned int hkey_event) > > mutex_unlock(&kbdlight_mutex); > } > + > + if (hkey_event == TP_HKEY_EV_THM_CSM_COMPLETED) > + dytc_lapmode_refresh(); > + > } > > static void hotkey_driver_event(const unsigned int scancode) > @@ -10280,6 +10383,10 @@ static struct ibm_init_struct ibms_init[] __initdata = { > .init = tpacpi_lcdshadow_init, > .data = &lcdshadow_driver_data, > }, > + { > + .init = tpacpi_dytc_init, > + .data = &dytc_driver_data, > + }, > }; > > static int __init set_ibm_param(const char *val, const struct kernel_param *kp) > -- > 2.26.2 > -- With Best Regards, Andy Shevchenko
