| Message ID | 20171027132051.sw5m5iboowlsrxxb@azrael (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 10/27/2017 03:20 PM, Marc CAPDEVILLE wrote: > On asus T100, Capella cm3218 chip is implemented as ambiant light > sensor. This chip expose an smbus ARA protocol device on standard > address 0x0c. The chip is not functional before all alerts are > acknowledged. > On asus T100, this device is enumerated on ACPI bus and the description > give tow I2C connection. The first is the connection to the ARA device two > and the second gives the real address of the device. Is there a document somewhere describing what this ARA stuff is and how it works? Is this "Project ARA"? > > So, on device probe,If the i2c address is the ARA address and the > device is enumerated via acpi, we lookup for the real address in > the ACPI resource list and change it in the client structure. > if an interrupt resource is given, and only for cm3218 chip, > we declare an smbus_alert device. > > Signed-off-by: Marc CAPDEVILLE <m.capdeville@no-log.org> [...] > +/* Get the real i2c address from acpi resources */ > +static int cm3218_acpi_get_address(struct i2c_client *client) > +{ > + int ret; > + struct acpi_device *adev; > + LIST_HEAD(res_list); > + struct resource_entry *res_entry; > + struct acpi_resource *ares; > + struct acpi_resource_i2c_serialbus *sb; > + > + adev = ACPI_COMPANION(&client->dev); > + if (!adev) > + return -ENODEV; > + > + ret = acpi_dev_get_resources(adev, > + &res_list, > + cm3218_filter_i2c_address, > + client); > + if (ret < 0) > + return ret; > + > + /* get first resource */ > + res_entry = list_entry(&res_list, struct resource_entry, node); > + ares = (struct acpi_resource *)res_entry->res; > + sb = &ares->data.i2c_serial_bus; > + > + /* set i2c address */ > + client->addr = sb->slave_address; > + client->flags &= ~I2C_CLIENT_TEN; I'm not convinced overwriting the address and flags is legal. Those are owned by the I2C core and should be read-only in the client driver. Maybe use i2c_new_dummy() to create a device for the new address? > + if (sb->access_mode == ACPI_I2C_10BIT_MODE) > + client->flags |= I2C_CLIENT_TEN; > + > + acpi_dev_free_resource_list(&res_list); > + > + return 0; > +} [...] -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 10/30/2017 11:54 AM, Lars-Peter Clausen wrote: > On 10/27/2017 03:20 PM, Marc CAPDEVILLE wrote: >> On asus T100, Capella cm3218 chip is implemented as ambiant light >> sensor. This chip expose an smbus ARA protocol device on standard >> address 0x0c. The chip is not functional before all alerts are >> acknowledged. >> On asus T100, this device is enumerated on ACPI bus and the description >> give tow I2C connection. The first is the connection to the ARA device > > two > >> and the second gives the real address of the device. > > Is there a document somewhere describing what this ARA stuff is and how it > works? Is this "Project ARA"? Found it: "Address Response Alert". Given that the ARA address 0x0c is an reserved address and should not be used for normal I2C devices I wonder if the I2C core shouldn't ignore it and get the correct address on its own when instantiating the I2C slave device? I'd assume that this issue is not specific to this particular device. > >> >> So, on device probe,If the i2c address is the ARA address and the >> device is enumerated via acpi, we lookup for the real address in >> the ACPI resource list and change it in the client structure. >> if an interrupt resource is given, and only for cm3218 chip, >> we declare an smbus_alert device. >> >> Signed-off-by: Marc CAPDEVILLE <m.capdeville@no-log.org> > [...] >> +/* Get the real i2c address from acpi resources */ >> +static int cm3218_acpi_get_address(struct i2c_client *client) >> +{ >> + int ret; >> + struct acpi_device *adev; >> + LIST_HEAD(res_list); >> + struct resource_entry *res_entry; >> + struct acpi_resource *ares; >> + struct acpi_resource_i2c_serialbus *sb; >> + >> + adev = ACPI_COMPANION(&client->dev); >> + if (!adev) >> + return -ENODEV; >> + >> + ret = acpi_dev_get_resources(adev, >> + &res_list, >> + cm3218_filter_i2c_address, >> + client); >> + if (ret < 0) >> + return ret; >> + >> + /* get first resource */ >> + res_entry = list_entry(&res_list, struct resource_entry, node); >> + ares = (struct acpi_resource *)res_entry->res; >> + sb = &ares->data.i2c_serial_bus; >> + >> + /* set i2c address */ >> + client->addr = sb->slave_address; >> + client->flags &= ~I2C_CLIENT_TEN; > > I'm not convinced overwriting the address and flags is legal. Those are > owned by the I2C core and should be read-only in the client driver. Maybe > use i2c_new_dummy() to create a device for the new address? > >> + if (sb->access_mode == ACPI_I2C_10BIT_MODE) >> + client->flags |= I2C_CLIENT_TEN; >> + >> + acpi_dev_free_resource_list(&res_list); >> + >> + return 0; >> +} > [...] > -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
> Is there a document somewhere describing what this ARA stuff is and how it > works? Is this "Project ARA"? Check the SMBus specs for "Alert Response Address". Note: This is general info, I haven't checked this driver at all.
Hi Marc,
Thank you for the patch! Perhaps something to improve:
[auto build test WARNING on iio/togreg]
[also build test WARNING on v4.14-rc7 next-20171018]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Marc-CAPDEVILLE/iio-Add-cm3218-smbus-ara-and-acpi-support/20171030-195025
base: https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg
config: x86_64-randconfig-b0-10311428 (attached as .config)
compiler: gcc-4.4 (Debian 4.4.7-8) 4.4.7
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64
All warnings (new ones prefixed by >>):
drivers/iio/light/cm32181.c: In function 'cm32181_probe':
drivers/iio/light/cm32181.c:424: error: 'clients' undeclared (first use in this function)
drivers/iio/light/cm32181.c:424: error: (Each undeclared identifier is reported only once
drivers/iio/light/cm32181.c:424: error: for each function it appears in.)
>> drivers/iio/light/cm32181.c:391: warning: unused variable 'ara_setup'
vim +/ara_setup +391 drivers/iio/light/cm32181.c
384
385 static int cm32181_probe(struct i2c_client *client,
386 const struct i2c_device_id *id)
387 {
388 struct cm32181_chip *cm32181;
389 struct iio_dev *indio_dev;
390 int ret;
> 391 struct i2c_smbus_alert_setup ara_setup;
392 const struct of_device_id *of_id;
393 const struct acpi_device_id *acpi_id;
394
395 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*cm32181));
396 if (!indio_dev) {
397 dev_err(&client->dev, "devm_iio_device_alloc failed\n");
398 return -ENOMEM;
399 }
400
401 cm32181 = iio_priv(indio_dev);
402 i2c_set_clientdata(client, indio_dev);
403 cm32181->client = client;
404
405 mutex_init(&cm32181->lock);
406 indio_dev->dev.parent = &client->dev;
407 indio_dev->channels = cm32181_channels;
408 indio_dev->num_channels = ARRAY_SIZE(cm32181_channels);
409 indio_dev->info = &cm32181_info;
410 indio_dev->name = id->name;
411 indio_dev->modes = INDIO_DIRECT_MODE;
412
413 /* Lookup for chip ID from platform, acpi or of device table */
414 if (id) {
415 cm32181->chip_id = id->driver_data;
416 } else if (ACPI_COMPANION(&client->dev)) {
417 acpi_id = acpi_match_device(client->dev.driver->acpi_match_table,
418 &client->dev);
419 if (!acpi_id)
420 return -ENODEV;
421
422 cm32181->chip_id = (kernel_ulong_t)acpi_id->driver_data;
423 } else if (client->dev.of_node) {
> 424 of_id = of_match_device(clients->dev.driver->of_match_table,
425 &client->dev);
426 if (!of_id)
427 return -ENODEV;
428
429 cm32181->chip_id = (kernel_ulong_t)of_id->data;
430 } else {
431 return -ENODEV;
432 }
433
434 if (cm32181->chip_id == CM3218_ID) {
435 if (client->addr == CM3218_ARA_ADDR) {
436 /*
437 * In case first address is the ARA device
438 * lookup for a second one in acpi resources if
439 * this client is enumerated on acpi
440 */
441 ret = cm3218_acpi_get_address(client);
442 if (ret < 0)
443 return -ENODEV;
444 }
445
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
diff --git a/drivers/iio/light/cm32181.c b/drivers/iio/light/cm32181.c index d6fd0dace74f..f1a7495e851b 100644 --- a/drivers/iio/light/cm32181.c +++ b/drivers/iio/light/cm32181.c @@ -18,8 +18,12 @@ #include <linux/iio/sysfs.h> #include <linux/iio/events.h> #include <linux/init.h> +#include <linux/i2c-smbus.h> +#include <linux/acpi.h> +#include <linux/of_device.h> +#include <linux/resource_ext.h> -/* Registers Address */ +/* Registers Addresses */ #define CM32181_REG_ADDR_CMD 0x00 #define CM32181_REG_ADDR_ALS 0x04 #define CM32181_REG_ADDR_STATUS 0x06 @@ -45,18 +49,25 @@ #define CM32181_MLUX_PER_BIT_BASE_IT 800000 /* Based on IT=800ms */ #define CM32181_CALIBSCALE_DEFAULT 1000 #define CM32181_CALIBSCALE_RESOLUTION 1000 -#define MLUX_PER_LUX 1000 +#define CM32181_MLUX_PER_LUX 1000 + +#define CM32181_ID 0x81 +#define CM3218_ID 0x18 + +#define CM3218_ARA_ADDR 0x0c static const u8 cm32181_reg[CM32181_CONF_REG_NUM] = { CM32181_REG_ADDR_CMD, }; -static const int als_it_bits[] = {12, 8, 0, 1, 2, 3}; -static const int als_it_value[] = {25000, 50000, 100000, 200000, 400000, +static const int cm32181_als_it_bits[] = {12, 8, 0, 1, 2, 3}; +static const int cm32181_als_it_value[] = {25000, 50000, 100000, 200000, 400000, 800000}; struct cm32181_chip { struct i2c_client *client; + int chip_id; + struct i2c_client *ara; struct mutex lock; u16 conf_regs[CM32181_CONF_REG_NUM]; int calibscale; @@ -81,7 +92,7 @@ static int cm32181_reg_init(struct cm32181_chip *cm32181) return ret; /* check device ID */ - if ((ret & 0xFF) != 0x81) + if ((ret & 0xFF) != cm32181->chip_id) return -ENODEV; /* Default Values */ @@ -103,7 +114,7 @@ static int cm32181_reg_init(struct cm32181_chip *cm32181) /** * cm32181_read_als_it() - Get sensor integration time (ms) * @cm32181: pointer of struct cm32181 - * @val2: pointer of int to load the als_it value. + * @val2: pointer of int to load the cm32181_als_it value. * * Report the current integartion time by millisecond. * @@ -117,9 +128,9 @@ static int cm32181_read_als_it(struct cm32181_chip *cm32181, int *val2) als_it = cm32181->conf_regs[CM32181_REG_ADDR_CMD]; als_it &= CM32181_CMD_ALS_IT_MASK; als_it >>= CM32181_CMD_ALS_IT_SHIFT; - for (i = 0; i < ARRAY_SIZE(als_it_bits); i++) { - if (als_it == als_it_bits[i]) { - *val2 = als_it_value[i]; + for (i = 0; i < ARRAY_SIZE(cm32181_als_it_bits); i++) { + if (als_it == cm32181_als_it_bits[i]) { + *val2 = cm32181_als_it_value[i]; return IIO_VAL_INT_PLUS_MICRO; } } @@ -142,14 +153,14 @@ static int cm32181_write_als_it(struct cm32181_chip *cm32181, int val) u16 als_it; int ret, i, n; - n = ARRAY_SIZE(als_it_value); + n = ARRAY_SIZE(cm32181_als_it_value); for (i = 0; i < n; i++) - if (val <= als_it_value[i]) + if (val <= cm32181_als_it_value[i]) break; if (i >= n) i = n - 1; - als_it = als_it_bits[i]; + als_it = cm32181_als_it_bits[i]; als_it <<= CM32181_CMD_ALS_IT_SHIFT; mutex_lock(&cm32181->lock); @@ -195,7 +206,7 @@ static int cm32181_get_lux(struct cm32181_chip *cm32181) lux *= ret; lux *= cm32181->calibscale; lux /= CM32181_CALIBSCALE_RESOLUTION; - lux /= MLUX_PER_LUX; + lux /= CM32181_MLUX_PER_LUX; if (lux > 0xFFFF) lux = 0xFFFF; @@ -263,9 +274,9 @@ static ssize_t cm32181_get_it_available(struct device *dev, { int i, n, len; - n = ARRAY_SIZE(als_it_value); + n = ARRAY_SIZE(cm32181_als_it_value); for (i = 0, len = 0; i < n; i++) - len += sprintf(buf + len, "0.%06u ", als_it_value[i]); + len += sprintf(buf + len, "0.%06u ", cm32181_als_it_value[i]); return len + sprintf(buf + len, "\n"); } @@ -298,12 +309,89 @@ static const struct iio_info cm32181_info = { .attrs = &cm32181_attribute_group, }; +#if defined(CONFIG_ACPI) +/* Filter acpi resources for a real i2c address on same adapter */ +static int cm3218_filter_i2c_address(struct acpi_resource *ares, void *data) +{ + struct i2c_client *client = data; + struct acpi_resource_i2c_serialbus *sb; + acpi_status status; + acpi_handle adapter_handle; + + if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) + return 1; + + sb = &ares->data.i2c_serial_bus; + if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) + return 1; + + status = acpi_get_handle(ACPI_HANDLE(&client->dev), + sb->resource_source.string_ptr, + &adapter_handle); + if (ACPI_FAILURE(status)) + return status; + + if (adapter_handle != ACPI_HANDLE(&client->adapter->dev)) + return 1; + + if (sb->slave_address == CM3218_ARA_ADDR) + return 1; + + return AE_OK; +} + +/* Get the real i2c address from acpi resources */ +static int cm3218_acpi_get_address(struct i2c_client *client) +{ + int ret; + struct acpi_device *adev; + LIST_HEAD(res_list); + struct resource_entry *res_entry; + struct acpi_resource *ares; + struct acpi_resource_i2c_serialbus *sb; + + adev = ACPI_COMPANION(&client->dev); + if (!adev) + return -ENODEV; + + ret = acpi_dev_get_resources(adev, + &res_list, + cm3218_filter_i2c_address, + client); + if (ret < 0) + return ret; + + /* get first resource */ + res_entry = list_entry(&res_list, struct resource_entry, node); + ares = (struct acpi_resource *)res_entry->res; + sb = &ares->data.i2c_serial_bus; + + /* set i2c address */ + client->addr = sb->slave_address; + client->flags &= ~I2C_CLIENT_TEN; + if (sb->access_mode == ACPI_I2C_10BIT_MODE) + client->flags |= I2C_CLIENT_TEN; + + acpi_dev_free_resource_list(&res_list); + + return 0; +} +#else +static inline int cm3218_acpi_get_address(struct i2c_client *client) +{ + return -ENODEV; +} +#endif + static int cm32181_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct cm32181_chip *cm32181; struct iio_dev *indio_dev; int ret; + struct i2c_smbus_alert_setup ara_setup; + const struct of_device_id *of_id; + const struct acpi_device_id *acpi_id; indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*cm32181)); if (!indio_dev) { @@ -323,11 +411,65 @@ static int cm32181_probe(struct i2c_client *client, indio_dev->name = id->name; indio_dev->modes = INDIO_DIRECT_MODE; + /* Lookup for chip ID from platform, acpi or of device table */ + if (id) { + cm32181->chip_id = id->driver_data; + } else if (ACPI_COMPANION(&client->dev)) { + acpi_id = acpi_match_device(client->dev.driver->acpi_match_table, + &client->dev); + if (!acpi_id) + return -ENODEV; + + cm32181->chip_id = (kernel_ulong_t)acpi_id->driver_data; + } else if (client->dev.of_node) { + of_id = of_match_device(clients->dev.driver->of_match_table, + &client->dev); + if (!of_id) + return -ENODEV; + + cm32181->chip_id = (kernel_ulong_t)of_id->data; + } else { + return -ENODEV; + } + + if (cm32181->chip_id == CM3218_ID) { + if (client->addr == CM3218_ARA_ADDR) { + /* + * In case first address is the ARA device + * lookup for a second one in acpi resources if + * this client is enumerated on acpi + */ + ret = cm3218_acpi_get_address(client); + if (ret < 0) + return -ENODEV; + } + +#ifdef CONFIG_I2C_SMBUS + if (client->irq > 0) { + /* setup smb alert device */ + ara_setup.irq = client->irq; + ara_setup.alert_edge_triggered = 0; + cm32181->ara = i2c_setup_smbus_alert(client->adapter, + &ara_setup); + if (!cm32181->ara) + return -ENODEV; + } else { + return -ENODEV; + } +#else + return -ENODEV; +#endif + } + ret = cm32181_reg_init(cm32181); if (ret) { dev_err(&client->dev, "%s: register init failed\n", __func__); + + if (cm32181->ara) + i2c_unregister_device(cm32181->ara); + return ret; } @@ -336,32 +478,58 @@ static int cm32181_probe(struct i2c_client *client, dev_err(&client->dev, "%s: regist device failed\n", __func__); + + if (cm32181->ara) + i2c_unregister_device(cm32181->ara); + return ret; } return 0; } +static int cm32181_remove(struct i2c_client *client) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(client); + struct cm32181_chip *cm32181 = iio_priv(indio_dev); + + if (cm32181->ara) + i2c_unregister_device(cm32181->ara); + + return 0; +}; + static const struct i2c_device_id cm32181_id[] = { - { "cm32181", 0 }, + { "cm32181", CM32181_ID }, + { "cm3218", CM3218_ID }, { } }; MODULE_DEVICE_TABLE(i2c, cm32181_id); static const struct of_device_id cm32181_of_match[] = { - { .compatible = "capella,cm32181" }, + { .compatible = "capella,cm32181", (void *)CM32181_ID }, + { .compatible = "capella,cm3218", (void *)CM3218_ID }, { } }; MODULE_DEVICE_TABLE(of, cm32181_of_match); +static const struct acpi_device_id cm32181_acpi_match[] = { + { "CPLM3218", CM3218_ID }, + { } +}; + +MODULE_DEVICE_TABLE(acpi, cm32181_acpi_match); + static struct i2c_driver cm32181_driver = { .driver = { .name = "cm32181", .of_match_table = of_match_ptr(cm32181_of_match), + .acpi_match_table = ACPI_PTR(cm32181_acpi_match), }, .id_table = cm32181_id, .probe = cm32181_probe, + .remove = cm32181_remove, }; module_i2c_driver(cm32181_driver);
On asus T100, Capella cm3218 chip is implemented as ambiant light sensor. This chip expose an smbus ARA protocol device on standard address 0x0c. The chip is not functional before all alerts are acknowledged. On asus T100, this device is enumerated on ACPI bus and the description give tow I2C connection. The first is the connection to the ARA device and the second gives the real address of the device. So, on device probe,If the i2c address is the ARA address and the device is enumerated via acpi, we lookup for the real address in the ACPI resource list and change it in the client structure. if an interrupt resource is given, and only for cm3218 chip, we declare an smbus_alert device. Signed-off-by: Marc CAPDEVILLE <m.capdeville@no-log.org> --- Thanks to all for your review. It seems that capellamicro.com mailhost timeout when sending to Kevin. v3 : - rework acpi i2c adress lookup - comment style cleanup - add prefix cm32181_to constantes and macros v2 : - cm3218 support always build - Cleanup of unneeded #if statement - Beter identifying chip in platform device, acpi and of_device drivers/iio/light/cm32181.c | 202 ++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 185 insertions(+), 17 deletions(-)