Hi, +Rob Rob I used your old email, sorry about that. <snip> >>>> The Qualcomm QPNP PMIC chips are components used with the >>>> Snapdragon 800 series SoC family. This driver exists >>>> largely as a glue mfd component, it exists to be an owner >>>> of an SPMI regmap for children devices described in >>>> device tree. >>>> >>>> Signed-off-by: Josh Cartwright <joshc@xxxxxxxxxxxxxx> >>>> Signed-off-by: Stanimir Varbanov <svarbanov@xxxxxxxxxx> >>>> --- >>>> drivers/mfd/Kconfig | 15 ++++++ >>>> drivers/mfd/Makefile | 1 + >>>> drivers/mfd/qpnp-spmi.c | 129 +++++++++++++++++++++++++++++++++++++++++++++++ >>>> 3 files changed, 145 insertions(+), 0 deletions(-) >>>> create mode 100644 drivers/mfd/qpnp-spmi.c >>>> >>>> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig >>>> index ee8204c..258b733 100644 >>>> --- a/drivers/mfd/Kconfig >>>> +++ b/drivers/mfd/Kconfig >>>> @@ -524,6 +524,21 @@ config MFD_PM8921_CORE >>>> Say M here if you want to include support for PM8921 chip as a module. >>>> This will build a module called "pm8921-core". >>>> >>>> +config MFD_QPNP_SPMI >>>> + tristate "Qualcomm QPNP SPMI PMIC" >>>> + depends on ARCH_QCOM || COMPILE_TEST >>>> + depends on OF >>>> + select MFD_CORE >>>> + select REGMAP_SPMI >>>> + help >>>> + This enables support for the Qualcomm QPNP SPMI PMICs. >>>> + These PMICs are currently used with the Snapdragon 800 series of >>>> + SoCs. Note, that this will only be useful paired with descriptions >>>> + of the independent functions as children nodes in the device tree. >>> <snip> >>> >>>> + * This program is distributed in the hope that it will be useful, >>>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of >>>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >>>> + * GNU General Public License for more details. >>>> + */ >>>> +#include <linux/kernel.h> >>>> +#include <linux/module.h> >>>> +#include <linux/spmi.h> >>>> +#include <linux/regmap.h> >>>> +#include <linux/of_address.h> >>>> +#include <linux/slab.h> >>>> +#include <linux/mfd/core.h> >>>> + >>>> +#define QPNP_RESOURCE_SIZE 256 >>>> + >>>> +static const struct regmap_config qpnp_regmap_config = { >>>> + .reg_bits = 16, >>>> + .val_bits = 8, >>>> + .max_register = 0xffff, >>>> +}; >>>> + >>>> +static int qpnp_index_to_resource(struct device_node *np, int index, >>>> + struct resource *res) >>>> +{ >>>> + const char *name = NULL; >>>> + const __be32 *addrp; >>>> + u64 addr; >>>> + >>>> + addrp = of_get_address(np, index, NULL, NULL); >>>> + if (!addrp) >>>> + return -EINVAL; >>>> + >>>> + addr = of_read_number(addrp, 1); >>>> + if (addr == OF_BAD_ADDR) >>>> + return -EINVAL; >>>> + >>>> + of_property_read_string_index(np, "reg-names", index, &name); >>>> + >>>> + res->start = addr; >>>> + res->end = addr + QPNP_RESOURCE_SIZE - 1; >>>> + res->flags = IORESOURCE_REG; >>>> + res->name = name ? name : np->name; >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static int qpnp_add_device(struct spmi_device *root, struct device_node *child) >>>> +{ >>>> + struct mfd_cell cell = {}; >>>> + struct resource *res, *r; >>>> + int num_resources = 0; >>>> + const char *compat; >>>> + int ret, i; >>>> + >>>> + compat = of_get_property(child, "compatible", NULL); >>>> + if (!compat) >>>> + return -ENODEV; >>>> + >>>> + while (of_get_address(child, num_resources, NULL, NULL)) >>>> + num_resources++; >>>> + >>>> + if (!num_resources) >>>> + return -ENODEV; >>>> + >>>> + res = kcalloc(num_resources, sizeof(*res), GFP_KERNEL); >>>> + if (!res) >>>> + return -ENOMEM; >>>> + >>>> + r = res; >>>> + for (i = 0; i < num_resources; i++, r++) >>>> + qpnp_index_to_resource(child, i, r); >>>> + >>>> + cell.name = kasprintf(GFP_KERNEL, "%x.%04x.%s", root->usid, >>>> + (u16)res[0].start, child->name); >>>> + cell.of_compatible = compat; >>>> + cell.num_resources = num_resources; >>>> + cell.resources = res; >>>> + >>>> + ret = mfd_add_devices(&root->dev, PLATFORM_DEVID_NONE, &cell, 1, >>>> + NULL, 0, NULL); >>>> + >>>> + kfree(res); >>>> + kfree(cell.name); >>>> + >>>> + return ret; >>>> +} >>>> + >>>> +static int qpnp_probe(struct spmi_device *sdev) >>>> +{ >>>> + struct device_node *root = sdev->dev.of_node; >>>> + struct device_node *child; >>>> + struct regmap *regmap; >>>> + >>>> + regmap = devm_regmap_init_spmi_ext(sdev, &qpnp_regmap_config); >>>> + if (IS_ERR(regmap)) >>>> + return PTR_ERR(regmap); >>>> + >>>> + for_each_available_child_of_node(root, child) >>>> + qpnp_add_device(sdev, child); >>> >>> This entire driver looks like a re-write of of_platform_populate(). >>> >>> Why? >> >> of_platform_populate is not used because the PMIC function resources are >> non-translatable. You can see that the resources are of type >> IORESOURCE_REG (qpnp_index_to_resource()) not IORESOURCE_MEM or _IO. >> >> The whole point of this mfd driver is to parse devicetree to prepare >> resources for every child and create platform device for it through >> mfd_add_devices(). Then the PMIC function driver got its resources and >> use them as register addresses passed to regmap. These register accesses >> hits the SPMI controller which is the physical interface between PMIC's >> and SoC. > > I can't help but think that if this is required, it should be part of > the core OF code, rather than doing your own thing which looks > frighteningly like existing framework functionality. Lee, does it make sense to have a common of_mfd code for devicetree parsing? Is that discussed already? I mean presently the mfd_cell resources and number of resources are passed by the mfd_add_devices users. Is it possible to have common code which parses devicetree sub-nodes of the parent device_node and fill resources/create platform devices for them. Rob, Grant I hope you guys have something to say here? > > Either way, I'm going to need a DT Ack before I accept this. > Sure. -- regards, Stan -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html