diff options
author | Evan Green <evgreen@chromium.org> | 2020-11-18 15:40:25 -0800 |
---|---|---|
committer | Wolfram Sang <wsa@kernel.org> | 2021-01-17 12:52:58 +0100 |
commit | 98b2b712bc8592c4ad212449162e36e47761a46c (patch) | |
tree | dd89ea28a8d16d6ca29ba0a3bc18a2fcf719c6fa /drivers | |
parent | 19eb29b05cc6dd6842ddc475a45da6723428e927 (diff) | |
download | linux-98b2b712bc8592c4ad212449162e36e47761a46c.tar.bz2 |
i2c: i2c-mux-gpio: Enable this driver in ACPI land
Enable i2c-mux-gpio devices to be defined via ACPI. The idle-state
property translates directly to a fwnode_property_*() call. The child
reg property translates naturally into _ADR in ACPI.
The i2c-parent binding is a relic from the days when the bindings
dictated that all direct children of an I2C controller had to be I2C
devices. These days that's no longer required. The i2c-mux can sit as a
direct child of its parent controller, which is where it makes the most
sense from a hardware description perspective. For the ACPI
implementation we'll assume that's always how the i2c-mux-gpio is
instantiated.
Signed-off-by: Evan Green <evgreen@chromium.org>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/i2c/muxes/i2c-mux-gpio.c | 107 |
1 files changed, 79 insertions, 28 deletions
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c index caaa782b50d8..bac415a52b78 100644 --- a/drivers/i2c/muxes/i2c-mux-gpio.c +++ b/drivers/i2c/muxes/i2c-mux-gpio.c @@ -49,35 +49,85 @@ static int i2c_mux_gpio_deselect(struct i2c_mux_core *muxc, u32 chan) return 0; } -#ifdef CONFIG_OF -static int i2c_mux_gpio_probe_dt(struct gpiomux *mux, - struct platform_device *pdev) +#ifdef CONFIG_ACPI + +static int i2c_mux_gpio_get_acpi_adr(struct device *dev, + struct fwnode_handle *fwdev, + unsigned int *adr) + +{ + unsigned long long adr64; + acpi_status status; + + status = acpi_evaluate_integer(ACPI_HANDLE_FWNODE(fwdev), + METHOD_NAME__ADR, + NULL, &adr64); + + if (!ACPI_SUCCESS(status)) { + dev_err(dev, "Cannot get address\n"); + return -EINVAL; + } + + *adr = adr64; + if (*adr != adr64) { + dev_err(dev, "Address out of range\n"); + return -ERANGE; + } + + return 0; +} + +#else + +static int i2c_mux_gpio_get_acpi_adr(struct device *dev, + struct fwnode_handle *fwdev, + unsigned int *adr) +{ + return -EINVAL; +} + +#endif + +static int i2c_mux_gpio_probe_fw(struct gpiomux *mux, + struct platform_device *pdev) { struct device *dev = &pdev->dev; - struct device_node *np = pdev->dev.of_node; - struct device_node *adapter_np, *child; - struct i2c_adapter *adapter; + struct device_node *np = dev->of_node; + struct device_node *adapter_np; + struct i2c_adapter *adapter = NULL; + struct fwnode_handle *child; unsigned *values; - int i = 0; + int rc, i = 0; + + if (is_of_node(dev->fwnode)) { + if (!np) + return -ENODEV; - if (!np) - return -ENODEV; + adapter_np = of_parse_phandle(np, "i2c-parent", 0); + if (!adapter_np) { + dev_err(&pdev->dev, "Cannot parse i2c-parent\n"); + return -ENODEV; + } + adapter = of_find_i2c_adapter_by_node(adapter_np); + of_node_put(adapter_np); + + } else if (is_acpi_node(dev->fwnode)) { + /* + * In ACPI land the mux should be a direct child of the i2c + * bus it muxes. + */ + acpi_handle dev_handle = ACPI_HANDLE(dev->parent); - adapter_np = of_parse_phandle(np, "i2c-parent", 0); - if (!adapter_np) { - dev_err(&pdev->dev, "Cannot parse i2c-parent\n"); - return -ENODEV; + adapter = i2c_acpi_find_adapter_by_handle(dev_handle); } - adapter = of_find_i2c_adapter_by_node(adapter_np); - of_node_put(adapter_np); + if (!adapter) return -EPROBE_DEFER; mux->data.parent = i2c_adapter_id(adapter); put_device(&adapter->dev); - mux->data.n_values = of_get_child_count(np); - + mux->data.n_values = device_get_child_node_count(dev); values = devm_kcalloc(dev, mux->data.n_values, sizeof(*mux->data.values), GFP_KERNEL); @@ -86,24 +136,25 @@ static int i2c_mux_gpio_probe_dt(struct gpiomux *mux, return -ENOMEM; } - for_each_child_of_node(np, child) { - of_property_read_u32(child, "reg", values + i); + device_for_each_child_node(dev, child) { + if (is_of_node(child)) { + fwnode_property_read_u32(child, "reg", values + i); + + } else if (is_acpi_node(child)) { + rc = i2c_mux_gpio_get_acpi_adr(dev, child, values + i); + if (rc) + return rc; + } + i++; } mux->data.values = values; - if (of_property_read_u32(np, "idle-state", &mux->data.idle)) + if (fwnode_property_read_u32(dev->fwnode, "idle-state", &mux->data.idle)) mux->data.idle = I2C_MUX_GPIO_NO_IDLE; return 0; } -#else -static int i2c_mux_gpio_probe_dt(struct gpiomux *mux, - struct platform_device *pdev) -{ - return 0; -} -#endif static int i2c_mux_gpio_probe(struct platform_device *pdev) { @@ -119,7 +170,7 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev) return -ENOMEM; if (!dev_get_platdata(&pdev->dev)) { - ret = i2c_mux_gpio_probe_dt(mux, pdev); + ret = i2c_mux_gpio_probe_fw(mux, pdev); if (ret < 0) return ret; } else { |