Re: [PATCH v6 7/9] platform/x86: serial-multi-instantiate: Add SPI support

From: Hans de Goede
Date: Wed Feb 02 2022 - 03:55:57 EST


Hi,

On 2/1/22 16:02, Hans de Goede wrote:
> Hi,
>
> On 1/21/22 18:24, Stefan Binding wrote:
>> Add support for spi bus in serial-multi-instantiate driver
>>
>> Some peripherals can have either a I2C or a SPI connection
>> to the host (but not both) but use the same HID for both
>> types. So it is not possible to use the HID to determine
>> whether it is I2C or SPI. The driver must check the node
>> to see if it contains I2cSerialBus or SpiSerialBus entries.
>>
>> For backwards-compatibility with the existing nodes I2C is
>> checked first and if such entries are found ONLY I2C devices
>> are created. Since some existing nodes that were already
>> handled by this driver could also contain unrelated
>> SpiSerialBus nodes that were previously ignored, and this
>> preserves that behavior. If there is ever a need to handle
>> a node where both I2C and SPI devices must be instantiated
>> this can be added in future.
>>
>> Signed-off-by: Stefan Binding <sbinding@xxxxxxxxxxxxxxxxxxxxx>
>> ---
>> drivers/platform/x86/Kconfig | 2 +-
>> .../platform/x86/serial-multi-instantiate.c | 174 +++++++++++++++---
>> 2 files changed, 151 insertions(+), 25 deletions(-)
>>
>> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
>> index 2e656909a866..8d1eec208854 100644
>> --- a/drivers/platform/x86/Kconfig
>> +++ b/drivers/platform/x86/Kconfig
>> @@ -992,7 +992,7 @@ config TOPSTAR_LAPTOP
>>
>> config SERIAL_MULTI_INSTANTIATE
>> tristate "Serial bus multi instantiate pseudo device driver"
>> - depends on I2C && ACPI
>> + depends on I2C && SPI && ACPI
>> help
>> Some ACPI-based systems list multiple devices in a single ACPI
>> firmware-node. This driver will instantiate separate clients
>> diff --git a/drivers/platform/x86/serial-multi-instantiate.c b/drivers/platform/x86/serial-multi-instantiate.c
>> index 4cd6d72a0741..3f05385ca2cf 100644
>> --- a/drivers/platform/x86/serial-multi-instantiate.c
>> +++ b/drivers/platform/x86/serial-multi-instantiate.c
>> @@ -14,6 +14,7 @@
>> #include <linux/module.h>
>> #include <linux/platform_device.h>
>> #include <linux/property.h>
>> +#include <linux/spi/spi.h>
>> #include <linux/types.h>
>>
>> #define IRQ_RESOURCE_TYPE GENMASK(1, 0)
>> @@ -21,15 +22,28 @@
>> #define IRQ_RESOURCE_GPIO 1
>> #define IRQ_RESOURCE_APIC 2
>>
>> +enum smi_bus_type {
>> + SMI_I2C,
>> + SMI_SPI,
>> + SMI_AUTO_DETECT,
>> +};
>> +
>> struct smi_instance {
>> const char *type;
>> unsigned int flags;
>> int irq_idx;
>> };
>>
>> +struct smi_node {
>> + enum smi_bus_type bus_type;
>> + struct smi_instance instances[];
>> +};
>> +
>> struct smi {
>> int i2c_num;
>> + int spi_num;
>> struct i2c_client **i2c_devs;
>> + struct spi_device **spi_devs;
>> };
>>
>> static int smi_get_irq(struct platform_device *pdev, struct acpi_device *adev,
>> @@ -59,6 +73,95 @@ static void smi_devs_unregister(struct smi *smi)
>> {
>> while (smi->i2c_num > 0)
>> i2c_unregister_device(smi->i2c_devs[--smi->i2c_num]);
>> +
>> + while (smi->spi_num > 0)
>> + spi_unregister_device(smi->spi_devs[--smi->spi_num]);
>> +}
>> +
>> +/**
>> + * smi_spi_probe - Instantiate multiple SPI devices from inst array
>> + * @pdev: Platform device
>> + * @adev: ACPI device
>> + * @smi: Internal struct for Serial multi instantiate driver
>> + * @inst_array: Array of instances to probe
>> + *
>> + * Returns the number of SPI devices instantiate, Zero if none is found or a negative error code.
>> + */
>> +static int smi_spi_probe(struct platform_device *pdev, struct acpi_device *adev, struct smi *smi,
>> + const struct smi_instance *inst_array)
>> +{
>> + struct device *dev = &pdev->dev;
>> + struct spi_controller *ctlr;
>> + struct spi_device *spi_dev;
>> + char name[50];
>> + int i, ret, count;
>> +
>> + ret = acpi_spi_count_resources(adev);
>> + if (ret < 0)
>> + return ret;
>> + else if (!ret)
>> + return -ENODEV;
>> +
>> + count = ret;
>> +
>> + smi->spi_devs = devm_kcalloc(dev, count, sizeof(*smi->spi_devs), GFP_KERNEL);
>> + if (!smi->spi_devs)
>> + return -ENOMEM;
>> +
>> + for (i = 0; i < count && inst_array[i].type; i++) {
>> +
>> + spi_dev = acpi_spi_device_alloc(NULL, adev, i);
>> + if (IS_ERR(spi_dev)) {
>> + ret = PTR_ERR(spi_dev);
>> + dev_err_probe(dev, ret, "failed to allocate SPI device %s from ACPI: %d\n",
>> + dev_name(&adev->dev), ret);
>> + goto error;
>> + }
>> +
>> + ctlr = spi_dev->controller;
>> +
>> + strscpy(spi_dev->modalias, inst_array[i].type, sizeof(spi_dev->modalias));
>> +
>> + ret = smi_get_irq(pdev, adev, &inst_array[i]);
>> + if (ret < 0) {
>> + spi_dev_put(spi_dev);
>> + goto error;
>> + }
>> + spi_dev->irq = ret;
>> +
>> + snprintf(name, sizeof(name), "%s-%s-%s.%d", dev_name(&ctlr->dev), dev_name(dev),
>> + inst_array[i].type, i);
>> + spi_dev->dev.init_name = name;
>> +
>> + ret = spi_add_device(spi_dev);
>> + if (ret) {
>> + dev_err_probe(&ctlr->dev, ret,
>> + "failed to add SPI device %s from ACPI: %d\n",
>> + dev_name(&adev->dev), ret);
>> + spi_dev_put(spi_dev);
>> + goto error;
>> + }
>> +
>> + dev_dbg(dev, "SPI device %s using chip select %u", name, spi_dev->chip_select);
>> +
>> + smi->spi_devs[i] = spi_dev;
>> + smi->spi_num++;
>> + }
>> +
>> + if (smi->spi_num < count) {
>> + dev_dbg(dev, "Error finding driver, idx %d\n", i);
>> + ret = -ENODEV;
>> + goto error;
>> + }
>> +
>> + dev_info(dev, "Instantiated %d SPI devices.\n", smi->spi_num);
>> +
>> + return 0;
>> +error:
>> + smi_devs_unregister(smi);
>> +
>> + return ret;
>> +
>> }
>>
>> /**
>> @@ -126,8 +229,8 @@ static int smi_i2c_probe(struct platform_device *pdev, struct acpi_device *adev,
>>
>> static int smi_probe(struct platform_device *pdev)
>> {
>> - const struct smi_instance *inst_array;
>> struct device *dev = &pdev->dev;
>> + const struct smi_node *node;
>> struct acpi_device *adev;
>> struct smi *smi;
>>
>> @@ -135,8 +238,8 @@ static int smi_probe(struct platform_device *pdev)
>> if (!adev)
>> return -ENODEV;
>>
>> - inst_array = device_get_match_data(dev);
>> - if (!inst_array) {
>> + node = device_get_match_data(dev);
>> + if (!node) {
>> dev_dbg(dev, "Error ACPI match data is missing\n");
>> return -ENODEV;
>> }
>> @@ -147,7 +250,21 @@ static int smi_probe(struct platform_device *pdev)
>>
>> platform_set_drvdata(pdev, smi);
>>
>> - return smi_i2c_probe(pdev, adev, smi, inst_array);
>> + switch (node->bus_type) {
>> + case SMI_I2C:
>> + return smi_i2c_probe(pdev, adev, smi, node->instances);
>> + case SMI_SPI:
>> + return smi_spi_probe(pdev, adev, smi, node->instances);
>> + case SMI_AUTO_DETECT:
>> + if (i2c_acpi_client_count(adev) > 0)
>> + return smi_i2c_probe(pdev, adev, smi, node->instances);
>> + else
>> + return smi_spi_probe(pdev, adev, smi, node->instances);
>> + default:
>> + break;
>
> Please replace this break with : "return -EINVAL" (since we really
> should never hit this default case).
>
> With that fixed, please add my R-b to the next version:

Note since Mark has merged 1-4 and provided a tag + pull-req for those
changes (thank you Mark). I plan to merge the rest of this series
into pdx86/for-next later today (except for 8/9).

I'll add the "return -EINVAL" myself when merging, so there is no
need to send out a new version.

Regards,

Hans




>
> Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx>
>
> Regards,
>
> Hans
>
>
>> + }
>> +
>> + return 0; /* never reached */
>> }
>>
>> static int smi_remove(struct platform_device *pdev)
>> @@ -159,27 +276,36 @@ static int smi_remove(struct platform_device *pdev)
>> return 0;
>> }
>>
>> -static const struct smi_instance bsg1160_data[] = {
>> - { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
>> - { "bmc150_magn" },
>> - { "bmg160" },
>> - {}
>> +static const struct smi_node bsg1160_data = {
>> + .instances = {
>> + { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
>> + { "bmc150_magn" },
>> + { "bmg160" },
>> + {}
>> + },
>> + .bus_type = SMI_I2C,
>> };
>>
>> -static const struct smi_instance bsg2150_data[] = {
>> - { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
>> - { "bmc150_magn" },
>> - /* The resources describe a 3th client, but it is not really there. */
>> - { "bsg2150_dummy_dev" },
>> - {}
>> +static const struct smi_node bsg2150_data = {
>> + .instances = {
>> + { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
>> + { "bmc150_magn" },
>> + /* The resources describe a 3th client, but it is not really there. */
>> + { "bsg2150_dummy_dev" },
>> + {}
>> + },
>> + .bus_type = SMI_I2C,
>> };
>>
>> -static const struct smi_instance int3515_data[] = {
>> - { "tps6598x", IRQ_RESOURCE_APIC, 0 },
>> - { "tps6598x", IRQ_RESOURCE_APIC, 1 },
>> - { "tps6598x", IRQ_RESOURCE_APIC, 2 },
>> - { "tps6598x", IRQ_RESOURCE_APIC, 3 },
>> - {}
>> +static const struct smi_node int3515_data = {
>> + .instances = {
>> + { "tps6598x", IRQ_RESOURCE_APIC, 0 },
>> + { "tps6598x", IRQ_RESOURCE_APIC, 1 },
>> + { "tps6598x", IRQ_RESOURCE_APIC, 2 },
>> + { "tps6598x", IRQ_RESOURCE_APIC, 3 },
>> + {}
>> + },
>> + .bus_type = SMI_I2C,
>> };
>>
>> /*
>> @@ -187,9 +313,9 @@ static const struct smi_instance int3515_data[] = {
>> * drivers/acpi/scan.c: acpi_device_enumeration_by_parent().
>> */
>> static const struct acpi_device_id smi_acpi_ids[] = {
>> - { "BSG1160", (unsigned long)bsg1160_data },
>> - { "BSG2150", (unsigned long)bsg2150_data },
>> - { "INT3515", (unsigned long)int3515_data },
>> + { "BSG1160", (unsigned long)&bsg1160_data },
>> + { "BSG2150", (unsigned long)&bsg2150_data },
>> + { "INT3515", (unsigned long)&int3515_data },
>> { }
>> };
>> MODULE_DEVICE_TABLE(acpi, smi_acpi_ids);
>>