| Message ID | 20180809114046.21366-5-hdegoede@redhat.com |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | i2c-multi-instantiate pseudo driver | expand |
On Thu, Aug 9, 2018 at 1:40 PM, Hans de Goede <hdegoede@redhat.com> wrote: > On systems with ACPI instantiated i2c-clients, normally there is 1 fw_node > per i2c-device and that fw-node contains 1 I2cSerialBus resource for that 1 > i2c-device. > > But in some rare cases the manufacturer has decided to describe multiple > i2c-devices in a single ACPI fwnode with multiple I2cSerialBus resources. > > An earlier attempt to fix this in the i2c-core resulted in a lot of extra > code to support this corner-case. > > This commit introduces a new i2c-multi-instantiate driver which fixes this > in a different way. This new driver can be built as a module which will > only loaded on affected systems. > > This driver will instantiate a new i2c-client per I2cSerialBus resource, > using the driver_data from the acpi_device_id it is binding to to tell it > which chip-type (and optional irq-resource) to use when instantiating. > > Note this driver depends on a platform device being instantiated for the > ACPI fwnode, see the i2c_multi_instantiate_ids list of ACPI device-ids in > drivers/acpi/scan.c: acpi_device_enumeration_by_parent(). > > Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > Acked-by: Wolfram Sang <wsa@the-dreams.de> > Signed-off-by: Hans de Goede <hdegoede@redhat.com> > --- > Changes in v2: > -Rebase on top of 4.18-rc2 > > Changes in v3: > -Change from an i2c-driver using a hack to allow having multiple i2c clients > at the same address to a platform-driver > > Changes in v4: > -Tweak MAINTAINERS entry a bit > > Changes in v5: > -s/no_clients/num_clients/ > -Change patch Subject prefix to platform/x86 > > Changes in v6: > -s/irq_idx/gpio_irq_idx/ And this is the only patch that has changed in v6, right? Anyway, if you have further updates on top of this series, please send them as incremental patches. Thanks, Rafael
Hi, On 09-08-18 13:55, Rafael J. Wysocki wrote: > On Thu, Aug 9, 2018 at 1:40 PM, Hans de Goede <hdegoede@redhat.com> wrote: >> On systems with ACPI instantiated i2c-clients, normally there is 1 fw_node >> per i2c-device and that fw-node contains 1 I2cSerialBus resource for that 1 >> i2c-device. >> >> But in some rare cases the manufacturer has decided to describe multiple >> i2c-devices in a single ACPI fwnode with multiple I2cSerialBus resources. >> >> An earlier attempt to fix this in the i2c-core resulted in a lot of extra >> code to support this corner-case. >> >> This commit introduces a new i2c-multi-instantiate driver which fixes this >> in a different way. This new driver can be built as a module which will >> only loaded on affected systems. >> >> This driver will instantiate a new i2c-client per I2cSerialBus resource, >> using the driver_data from the acpi_device_id it is binding to to tell it >> which chip-type (and optional irq-resource) to use when instantiating. >> >> Note this driver depends on a platform device being instantiated for the >> ACPI fwnode, see the i2c_multi_instantiate_ids list of ACPI device-ids in >> drivers/acpi/scan.c: acpi_device_enumeration_by_parent(). >> >> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> >> Acked-by: Wolfram Sang <wsa@the-dreams.de> >> Signed-off-by: Hans de Goede <hdegoede@redhat.com> >> --- >> Changes in v2: >> -Rebase on top of 4.18-rc2 >> >> Changes in v3: >> -Change from an i2c-driver using a hack to allow having multiple i2c clients >> at the same address to a platform-driver >> >> Changes in v4: >> -Tweak MAINTAINERS entry a bit >> >> Changes in v5: >> -s/no_clients/num_clients/ >> -Change patch Subject prefix to platform/x86 >> >> Changes in v6: >> -s/irq_idx/gpio_irq_idx/ > > And this is the only patch that has changed in v6, right? Correct. > Anyway, if you have further updates on top of this series, please send > them as incremental patches. Ok, will do. Thanks & Regards, Hans
On Thursday, August 9, 2018 2:08:41 PM CEST Hans de Goede wrote: > Hi, > > On 09-08-18 13:55, Rafael J. Wysocki wrote: > > On Thu, Aug 9, 2018 at 1:40 PM, Hans de Goede <hdegoede@redhat.com> wrote: > >> On systems with ACPI instantiated i2c-clients, normally there is 1 fw_node > >> per i2c-device and that fw-node contains 1 I2cSerialBus resource for that 1 > >> i2c-device. > >> > >> But in some rare cases the manufacturer has decided to describe multiple > >> i2c-devices in a single ACPI fwnode with multiple I2cSerialBus resources. > >> > >> An earlier attempt to fix this in the i2c-core resulted in a lot of extra > >> code to support this corner-case. > >> > >> This commit introduces a new i2c-multi-instantiate driver which fixes this > >> in a different way. This new driver can be built as a module which will > >> only loaded on affected systems. > >> > >> This driver will instantiate a new i2c-client per I2cSerialBus resource, > >> using the driver_data from the acpi_device_id it is binding to to tell it > >> which chip-type (and optional irq-resource) to use when instantiating. > >> > >> Note this driver depends on a platform device being instantiated for the > >> ACPI fwnode, see the i2c_multi_instantiate_ids list of ACPI device-ids in > >> drivers/acpi/scan.c: acpi_device_enumeration_by_parent(). > >> > >> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > >> Acked-by: Wolfram Sang <wsa@the-dreams.de> > >> Signed-off-by: Hans de Goede <hdegoede@redhat.com> > >> --- > >> Changes in v2: > >> -Rebase on top of 4.18-rc2 > >> > >> Changes in v3: > >> -Change from an i2c-driver using a hack to allow having multiple i2c clients > >> at the same address to a platform-driver > >> > >> Changes in v4: > >> -Tweak MAINTAINERS entry a bit > >> > >> Changes in v5: > >> -s/no_clients/num_clients/ > >> -Change patch Subject prefix to platform/x86 > >> > >> Changes in v6: > >> -s/irq_idx/gpio_irq_idx/ > > > > And this is the only patch that has changed in v6, right? > > Correct. > > > Anyway, if you have further updates on top of this series, please send > > them as incremental patches. > > Ok, will do. The series has been applied, thanks!
diff --git a/MAINTAINERS b/MAINTAINERS index 9b377508f24f..dbe7836e4f6b 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -367,6 +367,12 @@ L: linux-acpi@vger.kernel.org S: Maintained F: drivers/acpi/arm64 +ACPI I2C MULTI INSTANTIATE DRIVER +M: Hans de Goede <hdegoede@redhat.com> +L: platform-driver-x86@vger.kernel.org +S: Maintained +F: drivers/platform/x86/i2c-multi-instantiate.c + ACPI PMIC DRIVERS M: "Rafael J. Wysocki" <rjw@rjwysocki.net> M: Len Brown <lenb@kernel.org> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig index 85a93453237c..64c82592d4b6 100644 --- a/drivers/platform/x86/Kconfig +++ b/drivers/platform/x86/Kconfig @@ -1219,6 +1219,17 @@ config INTEL_CHTDC_TI_PWRBTN To compile this driver as a module, choose M here: the module will be called intel_chtdc_ti_pwrbtn. +config I2C_MULTI_INSTANTIATE + tristate "I2C multi instantiate pseudo device driver" + depends on I2C && ACPI + help + Some ACPI-based systems list multiple i2c-devices in a single ACPI + firmware-node. This driver will instantiate separate i2c-clients + for each device in the firmware-node. + + To compile this driver as a module, choose M here: the module + will be called i2c-multi-instantiate. + endif # X86_PLATFORM_DEVICES config PMC_ATOM diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile index 8d9477114fb5..e6d1becf81ce 100644 --- a/drivers/platform/x86/Makefile +++ b/drivers/platform/x86/Makefile @@ -91,3 +91,4 @@ obj-$(CONFIG_PMC_ATOM) += pmc_atom.o obj-$(CONFIG_MLX_PLATFORM) += mlx-platform.o obj-$(CONFIG_INTEL_TURBO_MAX_3) += intel_turbo_max_3.o obj-$(CONFIG_INTEL_CHTDC_TI_PWRBTN) += intel_chtdc_ti_pwrbtn.o +obj-$(CONFIG_I2C_MULTI_INSTANTIATE) += i2c-multi-instantiate.o diff --git a/drivers/platform/x86/i2c-multi-instantiate.c b/drivers/platform/x86/i2c-multi-instantiate.c new file mode 100644 index 000000000000..5456581b473c --- /dev/null +++ b/drivers/platform/x86/i2c-multi-instantiate.c @@ -0,0 +1,132 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * I2C multi-instantiate driver, pseudo driver to instantiate multiple + * i2c-clients from a single fwnode. + * + * Copyright 2018 Hans de Goede <hdegoede@redhat.com> + */ + +#include <linux/acpi.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> + +struct i2c_inst_data { + const char *type; + int gpio_irq_idx; +}; + +struct i2c_multi_inst_data { + int num_clients; + struct i2c_client *clients[0]; +}; + +static int i2c_multi_inst_probe(struct platform_device *pdev) +{ + struct i2c_multi_inst_data *multi; + const struct acpi_device_id *match; + const struct i2c_inst_data *inst_data; + struct i2c_board_info board_info = {}; + struct device *dev = &pdev->dev; + struct acpi_device *adev; + char name[32]; + int i, ret; + + match = acpi_match_device(dev->driver->acpi_match_table, dev); + if (!match) { + dev_err(dev, "Error ACPI match data is missing\n"); + return -ENODEV; + } + inst_data = (const struct i2c_inst_data *)match->driver_data; + + adev = ACPI_COMPANION(dev); + + /* Count number of clients to instantiate */ + for (i = 0; inst_data[i].type; i++) {} + + multi = devm_kmalloc(dev, + offsetof(struct i2c_multi_inst_data, clients[i]), + GFP_KERNEL); + if (!multi) + return -ENOMEM; + + multi->num_clients = i; + + for (i = 0; i < multi->num_clients; i++) { + memset(&board_info, 0, sizeof(board_info)); + strlcpy(board_info.type, inst_data[i].type, I2C_NAME_SIZE); + snprintf(name, sizeof(name), "%s-%s", match->id, + inst_data[i].type); + board_info.dev_name = name; + board_info.irq = 0; + if (inst_data[i].gpio_irq_idx != -1) { + ret = acpi_dev_gpio_irq_get(adev, + inst_data[i].gpio_irq_idx); + if (ret < 0) { + dev_err(dev, "Error requesting irq at index %d: %d\n", + inst_data[i].gpio_irq_idx, ret); + goto error; + } + board_info.irq = ret; + } + multi->clients[i] = i2c_acpi_new_device(dev, i, &board_info); + if (!multi->clients[i]) { + dev_err(dev, "Error creating i2c-client, idx %d\n", i); + ret = -ENODEV; + goto error; + } + } + + platform_set_drvdata(pdev, multi); + return 0; + +error: + while (--i >= 0) + i2c_unregister_device(multi->clients[i]); + + return ret; +} + +static int i2c_multi_inst_remove(struct platform_device *pdev) +{ + struct i2c_multi_inst_data *multi = platform_get_drvdata(pdev); + int i; + + for (i = 0; i < multi->num_clients; i++) + i2c_unregister_device(multi->clients[i]); + + return 0; +} + +static const struct i2c_inst_data bsg1160_data[] = { + { "bmc150_accel", 0 }, + { "bmc150_magn", -1 }, + { "bmg160", -1 }, + {} +}; + +/* + * Note new device-ids must also be added to i2c_multi_instantiate_ids in + * drivers/acpi/scan.c: acpi_device_enumeration_by_parent(). + */ +static const struct acpi_device_id i2c_multi_inst_acpi_ids[] = { + { "BSG1160", (unsigned long)bsg1160_data }, + { } +}; +MODULE_DEVICE_TABLE(acpi, i2c_multi_inst_acpi_ids); + +static struct platform_driver i2c_multi_inst_driver = { + .driver = { + .name = "I2C multi instantiate pseudo device driver", + .acpi_match_table = ACPI_PTR(i2c_multi_inst_acpi_ids), + }, + .probe = i2c_multi_inst_probe, + .remove = i2c_multi_inst_remove, +}; +module_platform_driver(i2c_multi_inst_driver); + +MODULE_DESCRIPTION("I2C multi instantiate pseudo device driver"); +MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); +MODULE_LICENSE("GPL");