[PATCH] pinctrl: Add one-register-per-pin type device tree based pinctrl driver
Tony Lindgren
tony at atomide.com
Tue Jun 19 23:56:01 EST 2012
Hi,
Below is the pinctrl-single patch updated with hopefully all the Stephen's
comments addressed. The binding still needs to be looked at, see relevant
parts of the discussion below.
* Tony Lindgren <tony at atomide.com> [120617 22:55]:
> * Stephen Warren <swarren at wwwdotorg.org> [120615 09:21]:
> > On 06/15/2012 03:49 AM, Tony Lindgren wrote:
> >
> > (Arnd, Grant, Rob, CC'ing you mainly re: the very last set of comments
> > in this email; can you take a look at Tony's patch and comment on the
> > binding)
>
> Yes please take a look.
>
> > >> One final comment: A little while before Linaro Connect in San
> > >> Francisco, we were all having difficulty coming up with any kind of DT
> > >> binding for pinctrl. I had suggested the possibility of creating a
> > >> binding which just said "write value X to register Y, write value P to
> > >> register Q, ...". This was rejected at connect, because a raw list of
> > >> register writes didn't document anything or describe semantics - it was
> > >> too much of a binary blob. This driver seems to be doing almost the
> > >> exact same thing. In order to avoid that assertion, it'd need to truly
> > >> have individual representations of which pins exist, which pingroups
> > >> exist, which functions exist, and which functions can be selected onto
> > >> which pins/pingroups. That would be a radically different binding. I
> > >> wonder what's changed such that this kind of driver wasn't acceptable
> > >> then, but is now?
> > >
> > > Well that's why I had two bindings earlier: The current binding for the
> > > bulk pins that's faster to parse, and a more verbose binding for drivers that
> > > allows naming the functions.
> > >
> > > In your previous comments at [1] you seemed to prefer this current binding
> > > based on the "Why not only allow (1)?" comment. Maybe you had something else
> > > in mind, care to clarify that a bit too?
> >
> > Well, first I thought about semantics vs. just banging a register list a
> > tiny bit more, and remembered the previous discussion.
> >
> > But my comment at [1] wasn't so much about "why not just have a raw
> > register list", but more regarding why support two different
> > representations within the same binding; it wasn't really clear to me
> > from reading the original email what the difference between the two
> > representations; why have two representations, why/when-to use one vs.
> > the other, that the difference was about providing a "semantic" list of
> > pins/pingroups/functions vs. providing a "raw" register list.
>
> I too would prefer more verbose .dts files. Unfortunately the parsing of
> several hundred board specific pins adds quite a bit of overhead.
>
> > IIRC, the pushback on a raw "bang these registers" representation came
> > from Grant and/or Arnd. It'd be a good idea if they (and indeed Rob)
> > could comment on this binding proposal. If they're OK with this kind of
> > pretty raw representation, I'm not going to object, but I have a feeling
> > they might not like it?
>
> Yes let's see if anybody has better ideas.
>
> Regards,
>
> Tony
>
>
> > > [1] http://article.gmane.org/gmane.linux.kernel/1291838
From: Tony Lindgren <tony at atomide.com>
Date: Wed, 6 Jun 2012 04:18:18 -0700
Subject: [PATCH] pinctrl: Add one-register-per-pin type device tree based pinctrl driver
Add one-register-per-pin type device tree based pinctrl driver.
Currently this driver only works on omap2+ series of processors,
where there is either an 8 or 16-bit padconf register for each pin.
Support for other similar pinmux controllers can be added.
Signed-off-by: Tony Lindgren <tony at atomide.com>
diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-single.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-single.txt
new file mode 100644
index 0000000..929254c
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-single.txt
@@ -0,0 +1,106 @@
+One-register-per-pin type device tree based pinctrl driver
+
+Required properties:
+- compatible : "pinctrl-single"
+
+- reg : offset and length of the register set for the mux registers
+
+- pinctrl-single,register-width : pinmux register access width in bits
+
+- pinctrl-single,function-mask : mask of allowed pinmux function bits
+ in the pinmux register
+
+- pinctrl-single,pinconf-mask : mask of allowed pinconf bits in the
+ pinmux register; this gets combined with pinconf mask but is a separate
+ mask to allow the option of setting pinconf separatately from the
+ function
+
+- pinctrl-single,function-off : function off mode for disabled state if
+ available and same for all registers; if not, use a value larger than
+ function-mask to ignore disabling of registers
+
+This driver assumes that there is only one register for each pin,
+and uses the common pinctrl bindings as specified in the pinctrl-bindings.txt
+document in this directory.
+
+The pinctrl register offsets and default values are specified as pairs
+using pinctrl-single,pins. For example, setting a pin for a device
+could be done with:
+
+ pinctrl-single,pins = <0xdc 0x118>;
+
+Where 0xdc is the offset from the pinctrl register base address for the
+device pinctrl register, and 0x118 contains the desired value of the
+pinctrl register. See the device example and static board pins example
+below for more information.
+
+This driver tries to avoid understanding pin and function names because of
+the extra bloat they would cause especially in the case of a large number
+of pins. This driver just sets what is specified for the board in the .dts file.
+Further user space debugging tools can be developed to decipher the pin and
+function names using debugfs.
+
+Example:
+
+/* SoC common file */
+
+/* first controller instance for pins in core domain */
+pmx_core: pinmux at 4a100040 {
+ compatible = "pinctrl-single";
+ reg = <0x4a100040 0x0196>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ pinctrl-single,register-width = <16>;
+ pinctrl-single,function-mask = <0x7>;
+ pinctrl-single,function-off = <0xffffffff>;
+ pinctrl-single,pinconf-mask = <0xfff8>;
+};
+
+/* second controller instance for pins in wkup domain */
+pmx_wkup: pinmux at 4a31e040 {
+ compatible = "pinctrl-single;
+ reg = <0x4a31e040 0x0038>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ pinctrl-single,register-width = <16>;
+ pinctrl-single,function-mask = <0x7>;
+ pinctrl-single,function-off = <0xffffffff>;
+ pinctrl-single,pinconf-mask = <0xfff8>;
+};
+
+
+/* board specific .dts file */
+
+&pmx_core {
+
+ /*
+ * map all board specific static pins enabled by the pinctrl driver
+ * itself during the boot (or just set them up in the bootloader)
+ */
+ pinctrl-names = "default";
+ pinctrl-0 = <&board_pins>;
+
+ board_pins: pinmux_board_pins {
+ pinctrl-single,pins = <
+ 0x6c 0xf /* csi21_dx3 OUTPUT | MODE7 */
+ 0x6e 0xf /* csi21_dy3 OUTPUT | MODE7 */
+ 0x70 0xf /* csi21_dx4 OUTPUT | MODE7 */
+ 0x72 0xf /* csi21_dy4 OUTPUT | MODE7 */
+ >;
+ };
+
+ /* map uart2 pins */
+ uart2_pins: pinmux_uart2_pins {
+ pinctrl-single,pins = <
+ 0xd8 0x118 /* uart2_cts INPUT_PULLUP | MODE0 */
+ 0xda 0 /* uart2_rts OUTPUT | MODE0 */
+ 0xdc 0x118 /* uart2_rx INPUT_PULLUP | MODE0 */
+ 0xde 0 /* uart2_tx OUTPUT | MODE0 */
+ >;
+ };
+};
+
+&uart2 {
+ pinctrl-names = "default";
+ pinctrl-0 = <&uart2_pins>;
+};
diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index c6e6ae0..8071a31 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -102,6 +102,14 @@ config PINCTRL_PXA910
select PINCTRL_PXA3xx
select PINCONF
+config PINCTRL_SINGLE
+ tristate "One-register-per-pin type device tree based pinctrl driver"
+ depends on OF
+ select PINMUX
+ select PINCONF
+ help
+ This selects the device tree based generic pinctrl driver.
+
config PINCTRL_SIRF
bool "CSR SiRFprimaII pin controller driver"
depends on ARCH_PRIMA2
diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
index 8c07437..f40b1f8 100644
--- a/drivers/pinctrl/Makefile
+++ b/drivers/pinctrl/Makefile
@@ -22,6 +22,7 @@ obj-$(CONFIG_PINCTRL_NOMADIK) += pinctrl-nomadik.o
obj-$(CONFIG_PINCTRL_DB8500) += pinctrl-nomadik-db8500.o
obj-$(CONFIG_PINCTRL_PXA168) += pinctrl-pxa168.o
obj-$(CONFIG_PINCTRL_PXA910) += pinctrl-pxa910.o
+obj-$(CONFIG_PINCTRL_SINGLE) += pinctrl-single.o
obj-$(CONFIG_PINCTRL_SIRF) += pinctrl-sirf.o
obj-$(CONFIG_PINCTRL_TEGRA) += pinctrl-tegra.o
obj-$(CONFIG_PINCTRL_TEGRA20) += pinctrl-tegra20.o
diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c
new file mode 100644
index 0000000..76e83fb
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-single.c
@@ -0,0 +1,983 @@
+/*
+ * Generic device tree based pinctrl driver for one register per pin
+ * type pinmux controllers
+ *
+ * Copyright (C) 2012 Texas Instruments, Inc.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/list.h>
+
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/pinmux.h>
+
+#include "core.h"
+
+#define DRIVER_NAME "pinctrl-single"
+#define PCS_MUX_NAME "pinctrl-single,pins"
+#define PCS_REG_NAME_LEN ((sizeof(unsigned long) * 2) + 1)
+
+/**
+ * struct pcs_pingroup - pingroups for a function
+ * @np: pingroup device node pointer
+ * @name: pingroup name
+ * @gpins: array of the pins in the group
+ * @ngpins: number of pins in the group
+ * @node: list node
+ */
+struct pcs_pingroup {
+ struct device_node *np;
+ const char *name;
+ int *gpins;
+ int ngpins;
+ struct list_head node;
+};
+
+/**
+ * struct pcs_func_vals - mux function register offset and value pair
+ * @reg: register virtual address
+ * @val: register value
+ */
+struct pcs_func_vals {
+ void __iomem *reg;
+ unsigned val;
+};
+
+/**
+ * struct pcs_function - pinctrl function
+ * @name: pinctrl function name
+ * @vals: register and vals array
+ * @nvals: number of entries in vals array
+ * @pgnames: array of pingroup names the function uses
+ * @npgnames: number of pingroup names the function uses
+ * @node: list node
+ */
+struct pcs_function {
+ const char *name;
+ struct pcs_func_vals *vals;
+ unsigned nvals;
+ const char **pgnames;
+ int npgnames;
+ struct list_head node;
+};
+
+/**
+ * struct pcs_data - wrapper for data needed by pinctrl framework
+ * @pa: pindesc array
+ * @cur: index to current element
+ *
+ * REVISIT: We should be able to drop this eventually by adding
+ * support for registering pins individually in the pinctrl
+ * framework for those drivers that don't need a static array.
+ */
+struct pcs_data {
+ struct pinctrl_pin_desc *pa;
+ int cur;
+};
+
+/**
+ * struct pcs_name - register name for a pin
+ * @name: name of the pinctrl register
+ *
+ * REVISIT: We may want to make names optional in the pinctrl
+ * framework as some drivers may not care about pin names to
+ * avoid kernel bloat. The pin names can be deciphered by user
+ * space tools using debugfs based on the register address and
+ * SoC packaging information.
+ */
+struct pcs_name {
+ char name[PCS_REG_NAME_LEN];
+};
+
+/**
+ * struct pcs_device - mux device instance
+ * @res: resources
+ * @base: virtual address of the controller
+ * @size: size of the ioremapped area
+ * @dev: device entry
+ * @pctl: pin controller device
+ * @mutex: mutex protecting the lists
+ * @width: bits per mux register
+ * @fmask: function register mask
+ * @fshift: function register shift
+ * @foff: value to turn mux off
+ * @cmask: pinconf mask, separate from fmask to allow pin_config_set
+ * @fmax: max number of functions in fmask
+ * @names: array of register names for pins
+ * @pins: physical pins on the SoC
+ * @pgtree: pingroup index radix tree
+ * @ftree: function index radix tree
+ * @pingroups: list of pingroups
+ * @functions: list of functions
+ * @ngroups: number of pingroups
+ * @nfuncs: number of functions
+ * @desc: pin controller descriptor
+ * @read: register read function to use
+ * @write: register write function to use
+ */
+struct pcs_device {
+ struct resource *res;
+ void __iomem *base;
+ unsigned size;
+ struct device *dev;
+ struct pinctrl_dev *pctl;
+ struct mutex mutex;
+ unsigned width;
+ unsigned fmask;
+ unsigned fshift;
+ unsigned foff;
+ unsigned cmask;
+ unsigned fmax;
+ struct pcs_name *names;
+ struct pcs_data pins;
+ struct radix_tree_root pgtree;
+ struct radix_tree_root ftree;
+ struct list_head pingroups;
+ struct list_head functions;
+ unsigned ngroups;
+ unsigned nfuncs;
+ struct pinctrl_desc desc;
+ unsigned (*read)(void __iomem *reg);
+ void (*write)(unsigned val, void __iomem *reg);
+};
+
+/*
+ * REVISIT: Reads and writes could eventually use regmap or something
+ * generic. But at least on omaps, some mux registers are performance
+ * critical as they may need to be remuxed every time before and after
+ * idle. Adding tests for register access width for every read and
+ * write like regmap is doing is not desired, and caching the registers
+ * does not help in this case.
+ */
+
+static unsigned __maybe_unused pcs_readb(void __iomem *reg)
+{
+ return readb(reg);
+}
+
+static unsigned __maybe_unused pcs_readw(void __iomem *reg)
+{
+ return readw(reg);
+}
+
+static unsigned __maybe_unused pcs_readl(void __iomem *reg)
+{
+ return readl(reg);
+}
+
+static void __maybe_unused pcs_writeb(unsigned val, void __iomem *reg)
+{
+ writeb(val, reg);
+}
+
+static void __maybe_unused pcs_writew(unsigned val, void __iomem *reg)
+{
+ writew(val, reg);
+}
+
+static void __maybe_unused pcs_writel(unsigned val, void __iomem *reg)
+{
+ writel(val, reg);
+}
+
+static int pcs_get_groups_count(struct pinctrl_dev *pctldev)
+{
+ struct pcs_device *pcs;
+
+ pcs = pinctrl_dev_get_drvdata(pctldev);
+
+ return pcs->ngroups;
+}
+
+static const char *pcs_get_group_name(struct pinctrl_dev *pctldev,
+ unsigned gselector)
+{
+ struct pcs_device *pcs;
+ struct pcs_pingroup *group;
+
+ pcs = pinctrl_dev_get_drvdata(pctldev);
+ group = radix_tree_lookup(&pcs->pgtree, gselector);
+ if (!group) {
+ dev_err(pcs->dev, "%s could not find pingroup%i\n",
+ __func__, gselector);
+ return NULL;
+ }
+
+ return group->name;
+}
+
+static int pcs_get_group_pins(struct pinctrl_dev *pctldev,
+ unsigned gselector,
+ const unsigned **pins,
+ unsigned *npins)
+{
+ struct pcs_device *pcs;
+ struct pcs_pingroup *group;
+
+ pcs = pinctrl_dev_get_drvdata(pctldev);
+ group = radix_tree_lookup(&pcs->pgtree, gselector);
+ if (!group) {
+ dev_err(pcs->dev, "%s could not find pingroup%i\n",
+ __func__, gselector);
+ return -EINVAL;
+ }
+
+ *pins = group->gpins;
+ *npins = group->ngpins;
+
+ return 0;
+}
+
+static void pcs_pin_dbg_show(struct pinctrl_dev *pctldev,
+ struct seq_file *s,
+ unsigned offset)
+{
+ seq_printf(s, " " DRIVER_NAME);
+}
+
+static void pcs_dt_free_map(struct pinctrl_dev *pctldev,
+ struct pinctrl_map *map, unsigned num_maps)
+{
+ struct pcs_device *pcs;
+
+ pcs = pinctrl_dev_get_drvdata(pctldev);
+ devm_kfree(pcs->dev, map);
+}
+
+static int pcs_dt_node_to_map(struct pinctrl_dev *pctldev,
+ struct device_node *np_config,
+ struct pinctrl_map **map, unsigned *num_maps);
+
+static struct pinctrl_ops pcs_pinctrl_ops = {
+ .get_groups_count = pcs_get_groups_count,
+ .get_group_name = pcs_get_group_name,
+ .get_group_pins = pcs_get_group_pins,
+ .pin_dbg_show = pcs_pin_dbg_show,
+ .dt_node_to_map = pcs_dt_node_to_map,
+ .dt_free_map = pcs_dt_free_map,
+};
+
+static int pcs_get_functions_count(struct pinctrl_dev *pctldev)
+{
+ struct pcs_device *pcs;
+
+ pcs = pinctrl_dev_get_drvdata(pctldev);
+
+ return pcs->nfuncs;
+}
+
+static const char *pcs_get_function_name(struct pinctrl_dev *pctldev,
+ unsigned fselector)
+{
+ struct pcs_device *pcs;
+ struct pcs_function *func;
+
+ pcs = pinctrl_dev_get_drvdata(pctldev);
+ func = radix_tree_lookup(&pcs->ftree, fselector);
+ if (!func) {
+ dev_err(pcs->dev, "%s could not find function%i\n",
+ __func__, fselector);
+ return NULL;
+ }
+
+ return func->name;
+}
+
+static int pcs_get_function_groups(struct pinctrl_dev *pctldev,
+ unsigned fselector,
+ const char * const **groups,
+ unsigned * const ngroups)
+{
+ struct pcs_device *pcs;
+ struct pcs_function *func;
+
+ pcs = pinctrl_dev_get_drvdata(pctldev);
+ func = radix_tree_lookup(&pcs->ftree, fselector);
+ if (!func) {
+ dev_err(pcs->dev, "%s could not find function%i\n",
+ __func__, fselector);
+ return -EINVAL;
+ }
+ *groups = func->pgnames;
+ *ngroups = func->npgnames;
+
+ return 0;
+}
+
+static int pcs_enable(struct pinctrl_dev *pctldev, unsigned fselector,
+ unsigned group)
+{
+ struct pcs_device *pcs;
+ struct pcs_function *func;
+ int i;
+
+ pcs = pinctrl_dev_get_drvdata(pctldev);
+ func = radix_tree_lookup(&pcs->ftree, fselector);
+ if (!func)
+ return -EINVAL;
+
+ dev_dbg(pcs->dev, "enabling %s function%i\n",
+ func->name, fselector);
+
+ for (i = 0; i < func->nvals; i++) {
+ struct pcs_func_vals *vals;
+ unsigned val;
+
+ vals = &func->vals[i];
+ val = pcs->read(vals->reg);
+ val &= ~(pcs->cmask | pcs->fmask);
+ val |= vals->val;
+ pcs->write(val, vals->reg);
+ }
+
+ return 0;
+}
+
+static void pcs_disable(struct pinctrl_dev *pctldev, unsigned fselector,
+ unsigned group)
+{
+ struct pcs_device *pcs;
+ struct pcs_function *func;
+ int i;
+
+ pcs = pinctrl_dev_get_drvdata(pctldev);
+ func = radix_tree_lookup(&pcs->ftree, fselector);
+ if (!func) {
+ dev_err(pcs->dev, "%s could not find function%i\n",
+ __func__, fselector);
+ return;
+ }
+
+ /*
+ * Do not touch pinconf if function-off is larger than function-mask.
+ * Some hardware does not have clearly defined disable function, so we
+ * just ignore disable for those cases. For pin specific off modes,
+ * use alternate named states as described in pinctrl-bindings.txt.
+ */
+ if ((pcs->foff << pcs->fshift) > pcs->fshift) {
+ dev_dbg(pcs->dev, "ignoring disable for %s function%i\n",
+ func->name, fselector);
+ return;
+ }
+
+ dev_dbg(pcs->dev, "disabling function%i %s\n",
+ fselector, func->name);
+
+ for (i = 0; i < func->nvals; i++) {
+ struct pcs_func_vals *vals;
+ unsigned val;
+
+ vals = &func->vals[i];
+ val = pcs->read(vals->reg);
+ val &= ~(pcs->cmask | pcs->fmask);
+ val |= pcs->foff << pcs->fshift;
+ pcs->write(val, vals->reg);
+ }
+}
+
+static int pcs_request_gpio(struct pinctrl_dev *pctldev,
+ struct pinctrl_gpio_range *range, unsigned offset)
+{
+ return -ENOTSUPP;
+}
+
+static struct pinmux_ops pcs_pinmux_ops = {
+ .get_functions_count = pcs_get_functions_count,
+ .get_function_name = pcs_get_function_name,
+ .get_function_groups = pcs_get_function_groups,
+ .enable = pcs_enable,
+ .disable = pcs_disable,
+ .gpio_request_enable = pcs_request_gpio,
+};
+
+static int pcs_pinconf_get(struct pinctrl_dev *pctldev,
+ unsigned pin, unsigned long *config)
+{
+ return -ENOTSUPP;
+}
+
+static int pcs_pinconf_set(struct pinctrl_dev *pctldev,
+ unsigned pin, unsigned long config)
+{
+ return -ENOTSUPP;
+}
+
+static int pcs_pinconf_group_get(struct pinctrl_dev *pctldev,
+ unsigned group, unsigned long *config)
+{
+ return -ENOTSUPP;
+}
+
+static int pcs_pinconf_group_set(struct pinctrl_dev *pctldev,
+ unsigned group, unsigned long config)
+{
+ return -ENOTSUPP;
+}
+
+static void pcs_pinconf_dbg_show(struct pinctrl_dev *pctldev,
+ struct seq_file *s, unsigned offset)
+{
+}
+
+static void pcs_pinconf_group_dbg_show(struct pinctrl_dev *pctldev,
+ struct seq_file *s, unsigned selector)
+{
+}
+
+static struct pinconf_ops pcs_pinconf_ops = {
+ .pin_config_get = pcs_pinconf_get,
+ .pin_config_set = pcs_pinconf_set,
+ .pin_config_group_get = pcs_pinconf_group_get,
+ .pin_config_group_set = pcs_pinconf_group_set,
+ .pin_config_dbg_show = pcs_pinconf_dbg_show,
+ .pin_config_group_dbg_show = pcs_pinconf_group_dbg_show,
+};
+
+/**
+ * pcs_add_pin() - add a pin to the static per controller pin array
+ * @pcs: pcs driver instance
+ * @offset: register offset from base
+ */
+static int __devinit pcs_add_pin(struct pcs_device *pcs, unsigned offset)
+{
+ struct pinctrl_pin_desc *pin;
+ struct pcs_name *pn;
+ int i;
+
+ i = pcs->pins.cur;
+ if (i >= pcs->desc.npins) {
+ dev_err(pcs->dev, "too many pins, max %i\n",
+ pcs->desc.npins);
+ return -ENOMEM;
+ }
+
+ pin = &pcs->pins.pa[i];
+ pn = &pcs->names[i];
+ sprintf(pn->name, "%lx",
+ (unsigned long)pcs->res->start + offset);
+ pin->name = pn->name;
+ pin->number = i;
+ pcs->pins.cur++;
+
+ return i;
+}
+
+/**
+ * pcs_allocate_pin_table() - adds all the pins for the pinctrl driver
+ * @pcs: pcs driver instance
+ *
+ * In case of errors, resources are freed in pcs_free_resources.
+ *
+ * If your hardware needs holes in the address space, then just set
+ * up multiple driver instances.
+ */
+static int __devinit pcs_allocate_pin_table(struct pcs_device *pcs)
+{
+ int mux_bytes, nr_pins, i;
+
+ mux_bytes = pcs->width / BITS_PER_BYTE;
+ nr_pins = pcs->size / mux_bytes;
+
+ dev_dbg(pcs->dev, "allocating %i pins\n", nr_pins);
+ pcs->pins.pa = devm_kzalloc(pcs->dev,
+ sizeof(*pcs->pins.pa) * nr_pins,
+ GFP_KERNEL);
+ if (!pcs->pins.pa)
+ return -ENOMEM;
+
+ pcs->names = devm_kzalloc(pcs->dev,
+ sizeof(struct pcs_name) * nr_pins,
+ GFP_KERNEL);
+ if (!pcs->names)
+ return -ENOMEM;
+
+ pcs->desc.pins = pcs->pins.pa;
+ pcs->desc.npins = nr_pins;
+
+ for (i = 0; i < pcs->desc.npins; i++) {
+ unsigned offset;
+ int res;
+
+ offset = i * mux_bytes;
+ res = pcs_add_pin(pcs, offset);
+ if (res < 0) {
+ dev_err(pcs->dev, "error adding pins: %i\n", res);
+ return res;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * pcs_add_function() - adds a new function to the function list
+ * @pcs: pcs driver instance
+ * @np: device node of the mux entry
+ * @name: name of the function
+ * @vals: array of mux register value pairs used by the function
+ * @nvals: number of mux register value pairs
+ * @pgnames: array of pingroup names for the function
+ * @npgnames: number of pingroup names
+ */
+static struct pcs_function *pcs_add_function(struct pcs_device *pcs,
+ struct device_node *np,
+ const char *name,
+ struct pcs_func_vals *vals,
+ unsigned nvals,
+ const char **pgnames,
+ unsigned npgnames)
+{
+ struct pcs_function *function;
+
+ function = devm_kzalloc(pcs->dev, sizeof(*function), GFP_KERNEL);
+ if (!function)
+ return NULL;
+
+ function->name = name;
+ function->vals = vals;
+ function->nvals = nvals;
+ function->pgnames = pgnames;
+ function->npgnames = npgnames;
+
+ mutex_lock(&pcs->mutex);
+ list_add_tail(&function->node, &pcs->functions);
+ radix_tree_insert(&pcs->ftree, pcs->nfuncs, function);
+ pcs->nfuncs++;
+ mutex_unlock(&pcs->mutex);
+
+ return function;
+}
+
+static void pcs_remove_function(struct pcs_device *pcs,
+ struct pcs_function *function)
+{
+ int i;
+
+ mutex_lock(&pcs->mutex);
+ for (i = 0; i < pcs->nfuncs; i++) {
+ struct pcs_function *found;
+
+ found = radix_tree_lookup(&pcs->ftree, i);
+ if (found == function)
+ radix_tree_delete(&pcs->ftree, i);
+ }
+ list_del(&function->node);
+ mutex_unlock(&pcs->mutex);
+}
+
+/**
+ * pcs_add_pingroup() - add a pingroup to the pingroup list
+ * @pcs: pcs driver instance
+ * @np: device node of the mux entry
+ * @name: name of the pingroup
+ * @gpins: array of the pins that belong to the group
+ * @ngpins: number of pins in the group
+ */
+static int pcs_add_pingroup(struct pcs_device *pcs,
+ struct device_node *np,
+ const char *name,
+ int *gpins,
+ int ngpins)
+{
+ struct pcs_pingroup *pingroup;
+
+ pingroup = devm_kzalloc(pcs->dev, sizeof(*pingroup), GFP_KERNEL);
+ if (!pingroup)
+ return -ENOMEM;
+
+ pingroup->name = name;
+ pingroup->np = np;
+ pingroup->gpins = gpins;
+ pingroup->ngpins = ngpins;
+
+ mutex_lock(&pcs->mutex);
+ list_add_tail(&pingroup->node, &pcs->pingroups);
+ radix_tree_insert(&pcs->pgtree, pcs->ngroups, pingroup);
+ pcs->ngroups++;
+ mutex_unlock(&pcs->mutex);
+
+ return 0;
+}
+
+/**
+ * pcs_get_pin_by_offset() - get a pin index based on the register offset
+ * @pcs: pcs driver instance
+ * @offset: register offset from the base
+ *
+ * Note that this is OK as long as the pins are in a static array.
+ */
+static int pcs_get_pin_by_offset(struct pcs_device *pcs, unsigned offset)
+{
+ unsigned index;
+
+ if (offset >= pcs->size) {
+ dev_err(pcs->dev, "mux offset out of range: 0x%x (0x%x)\n",
+ offset, pcs->size);
+ return -EINVAL;
+ }
+
+ index = offset / (pcs->width / BITS_PER_BYTE);
+
+ return index;
+}
+
+/**
+ * smux_parse_one_pinctrl_entry() - parses a device tree mux entry
+ * @pcs: pinctrl driver instance
+ * @np: device node of the mux entry
+ * @map: map entry
+ * @pgnames: pingroup names
+ *
+ * Note that this currently supports only sets of one register + value.
+ *
+ * If you are concerned about the boot time, set up the static pins in
+ * the bootloader, and only set up selected pins as device tree entries.
+ */
+static int pcs_parse_one_pinctrl_entry(struct pcs_device *pcs,
+ struct device_node *np,
+ struct pinctrl_map **map,
+ const char **pgnames)
+{
+ struct pcs_func_vals *vals;
+ const __be32 *mux;
+ int size, rows, *pins, index = 0, found = 0, res = -ENOMEM;
+ struct pcs_function *function;
+
+ mux = of_get_property(np, PCS_MUX_NAME, &size);
+ if ((!mux) || (size < sizeof(*mux) * 2)) {
+ dev_err(pcs->dev, "bad data for mux %s\n",
+ np->name);
+ return -EINVAL;
+ }
+
+ size /= sizeof(*mux); /* Number of elements in array */
+ rows = size / 2; /* Each row is a key value pair */
+
+ vals = devm_kzalloc(pcs->dev, sizeof(*vals) * rows, GFP_KERNEL);
+ if (!vals)
+ return -ENOMEM;
+
+ pins = devm_kzalloc(pcs->dev, sizeof(*pins) * rows, GFP_KERNEL);
+ if (!pins)
+ goto free_vals;
+
+ while (index < size) {
+ unsigned offset, val;
+ int pin;
+
+ offset = be32_to_cpup(mux + index++);
+ val = be32_to_cpup(mux + index++);
+ vals[found].reg = pcs->base + offset;
+ vals[found].val = val;
+
+ pin = pcs_get_pin_by_offset(pcs, offset);
+ if (pin < 0) {
+ dev_err(pcs->dev,
+ "could not add functions for %s %ux\n",
+ np->name, offset);
+ break;
+ }
+ pins[found++] = pin;
+ }
+
+ pgnames[0] = np->name;
+ function = pcs_add_function(pcs, np, np->name, vals, found, pgnames, 1);
+ if (!function)
+ goto free_pins;
+
+ res = pcs_add_pingroup(pcs, np, np->name, pins, found);
+ if (res < 0)
+ goto free_function;
+
+ (*map)->type = PIN_MAP_TYPE_MUX_GROUP;
+ (*map)->data.mux.group = np->name;
+ (*map)->data.mux.function = np->name;
+
+ return 0;
+
+free_function:
+ pcs_remove_function(pcs, function);
+
+free_pins:
+ devm_kfree(pcs->dev, pins);
+
+free_vals:
+ devm_kfree(pcs->dev, vals);
+
+ return res;
+}
+/**
+ * pcs_dt_node_to_map() - allocates and parses pinctrl maps
+ * @pctldev: pinctrl instance
+ * @np_config: device tree pinmux entry
+ * @map: array of map entries
+ * @num_maps: number of maps
+ */
+static int pcs_dt_node_to_map(struct pinctrl_dev *pctldev,
+ struct device_node *np_config,
+ struct pinctrl_map **map, unsigned *num_maps)
+{
+ struct pcs_device *pcs;
+ const char **pgnames;
+ int ret;
+
+ pcs = pinctrl_dev_get_drvdata(pctldev);
+
+ *map = devm_kzalloc(pcs->dev, sizeof(**map), GFP_KERNEL);
+ if (!map)
+ return -ENOMEM;
+
+ *num_maps = 0;
+
+ pgnames = devm_kzalloc(pcs->dev, sizeof(*pgnames), GFP_KERNEL);
+ if (!pgnames) {
+ ret = -ENOMEM;
+ goto free_map;
+ }
+
+ ret = pcs_parse_one_pinctrl_entry(pcs, np_config, map, pgnames);
+ if (ret < 0) {
+ dev_err(pcs->dev, "no pins entries for %s\n",
+ np_config->name);
+ goto free_pgnames;
+ }
+ *num_maps = 1;
+
+ return 0;
+
+free_pgnames:
+ devm_kfree(pcs->dev, pgnames);
+free_map:
+ devm_kfree(pcs->dev, *map);
+
+ return ret;
+}
+
+/**
+ * pcs_free_funcs() - free memory used by functions
+ * @pcs: pcs driver instance
+ */
+static void pcs_free_funcs(struct pcs_device *pcs)
+{
+ struct list_head *pos, *tmp;
+ int i;
+
+ mutex_lock(&pcs->mutex);
+ for (i = 0; i < pcs->nfuncs; i++) {
+ struct pcs_function *func;
+
+ func = radix_tree_lookup(&pcs->ftree, i);
+ if (!func)
+ continue;
+ radix_tree_delete(&pcs->ftree, i);
+ }
+ list_for_each_safe(pos, tmp, &pcs->functions) {
+ struct pcs_function *function;
+
+ function = list_entry(pos, struct pcs_function, node);
+ list_del(&function->node);
+ }
+ mutex_unlock(&pcs->mutex);
+}
+
+/**
+ * pcs_free_pingroups() - free memory used by pingroups
+ * @pcs: pcs driver instance
+ */
+static void pcs_free_pingroups(struct pcs_device *pcs)
+{
+ struct list_head *pos, *tmp;
+ int i;
+
+ mutex_lock(&pcs->mutex);
+ for (i = 0; i < pcs->ngroups; i++) {
+ struct pcs_pingroup *pingroup;
+
+ pingroup = radix_tree_lookup(&pcs->pgtree, i);
+ if (!pingroup)
+ continue;
+ radix_tree_delete(&pcs->pgtree, i);
+ }
+ list_for_each_safe(pos, tmp, &pcs->pingroups) {
+ struct pcs_pingroup *pingroup;
+
+ pingroup = list_entry(pos, struct pcs_pingroup, node);
+ list_del(&pingroup->node);
+ }
+ mutex_unlock(&pcs->mutex);
+}
+
+/**
+ * pcs_free_resources() - free memory used by this driver
+ * @pcs: pcs driver instance
+ */
+static void pcs_free_resources(struct pcs_device *pcs)
+{
+ if (pcs->pctl)
+ pinctrl_unregister(pcs->pctl);
+
+ pcs_free_funcs(pcs);
+ pcs_free_pingroups(pcs);
+}
+
+#define PCS_GET_PROP_U32(name, reg, err) \
+ do { \
+ ret = of_property_read_u32(np, name, reg); \
+ if (ret) { \
+ dev_err(pcs->dev, err); \
+ return ret; \
+ } \
+ } while (0);
+
+static struct of_device_id pcs_of_match[];
+
+static int __devinit pcs_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ const struct of_device_id *match;
+ struct resource *res;
+ struct pcs_device *pcs;
+ int ret;
+
+ match = of_match_device(pcs_of_match, &pdev->dev);
+ if (!match)
+ return -EINVAL;
+
+ pcs = devm_kzalloc(&pdev->dev, sizeof(*pcs), GFP_KERNEL);
+ if (!pcs) {
+ dev_err(&pdev->dev, "could not allocate\n");
+ return -ENOMEM;
+ }
+ pcs->dev = &pdev->dev;
+ mutex_init(&pcs->mutex);
+ INIT_LIST_HEAD(&pcs->pingroups);
+ INIT_LIST_HEAD(&pcs->functions);
+
+ PCS_GET_PROP_U32("pinctrl-single,register-width", &pcs->width,
+ "register width not specified\n");
+
+ PCS_GET_PROP_U32("pinctrl-single,function-mask", &pcs->fmask,
+ "function register mask not specified\n");
+ pcs->fshift = ffs(pcs->fmask) - 1;
+ pcs->fmax = pcs->fmask >> pcs->fshift;
+
+ PCS_GET_PROP_U32("pinctrl-single,function-off", &pcs->foff,
+ "function off mode not specified\n");
+
+ PCS_GET_PROP_U32("pinctrl-single,pinconf-mask", &pcs->cmask,
+ "pinconf mask not specified\n");
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(pcs->dev, "could not get resource\n");
+ return -ENODEV;
+ }
+
+ pcs->res = devm_request_mem_region(pcs->dev, res->start,
+ resource_size(res), DRIVER_NAME);
+ if (!pcs->res) {
+ dev_err(pcs->dev, "could not get mem_region\n");
+ return -EBUSY;
+ }
+
+ pcs->size = resource_size(pcs->res);
+ pcs->base = devm_ioremap(pcs->dev, pcs->res->start, pcs->size);
+ if (!pcs->base) {
+ dev_err(pcs->dev, "could not ioremap\n");
+ return -ENODEV;
+ }
+
+ INIT_RADIX_TREE(&pcs->pgtree, GFP_KERNEL);
+ INIT_RADIX_TREE(&pcs->ftree, GFP_KERNEL);
+ platform_set_drvdata(pdev, pcs);
+
+ switch (pcs->width) {
+ case 8:
+ pcs->read = pcs_readb;
+ pcs->write = pcs_writeb;
+ break;
+ case 16:
+ pcs->read = pcs_readw;
+ pcs->write = pcs_writew;
+ break;
+ case 32:
+ pcs->read = pcs_readl;
+ pcs->write = pcs_writel;
+ break;
+ default:
+ break;
+ }
+
+ pcs->desc.name = DRIVER_NAME;
+ pcs->desc.pctlops = &pcs_pinctrl_ops;
+ pcs->desc.pmxops = &pcs_pinmux_ops;
+ pcs->desc.confops = &pcs_pinconf_ops;
+ pcs->desc.owner = THIS_MODULE;
+
+ ret = pcs_allocate_pin_table(pcs);
+ if (ret < 0)
+ goto free;
+
+ pcs->pctl = pinctrl_register(&pcs->desc, pcs->dev, pcs);
+ if (!pcs->pctl) {
+ dev_err(pcs->dev, "could not register single pinctrl driver\n");
+ ret = -EINVAL;
+ goto free;
+ }
+
+ dev_info(pcs->dev, "%i pins at pa %p size %u\n",
+ pcs->desc.npins, pcs->base, pcs->size);
+
+ return 0;
+
+free:
+ pcs_free_resources(pcs);
+
+ return ret;
+}
+
+static int __devexit pcs_remove(struct platform_device *pdev)
+{
+ struct pcs_device *pcs = platform_get_drvdata(pdev);
+
+ if (!pcs)
+ return 0;
+
+ pcs_free_resources(pcs);
+
+ return 0;
+}
+
+static struct of_device_id pcs_of_match[] __devinitdata = {
+ { .compatible = DRIVER_NAME, },
+ { },
+};
+MODULE_DEVICE_TABLE(of, pcs_of_match);
+
+static struct platform_driver pcs_driver = {
+ .probe = pcs_probe,
+ .remove = __devexit_p(pcs_remove),
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = DRIVER_NAME,
+ .of_match_table = pcs_of_match,
+ },
+};
+
+module_platform_driver(pcs_driver);
+
+MODULE_AUTHOR("Tony Lindgren <tony at atomide.com>");
+MODULE_DESCRIPTION("One-register-per-pin type device tree based pinctrl driver");
+MODULE_LICENSE("GPL v2");
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