* [PATCH V2 2/3] of: Create function for counting number of phandles in a property
2013-02-12 17:59 [PATCH V2 1/3] of/selftest: Fix GPIOs selftest to cover the 7th case Grant Likely
@ 2013-02-12 17:59 ` Grant Likely
2013-02-12 17:59 ` [PATCH V2 3/3] gpio: Make of_count_named_gpios() use new of_count_phandle_with_args() Grant Likely
1 sibling, 0 replies; 3+ messages in thread
From: Grant Likely @ 2013-02-12 17:59 UTC (permalink / raw)
To: linux-kernel, devicetree-discuss
Cc: Grant Likely, Linus Walleij, Rob Herring, Andreas Larsson
This patch creates of_count_phandle_with_args(), a new function for
counting the number of phandle+argument tuples in a given property. This
is better than the existing method of parsing each phandle individually
until parsing fails which is a horribly slow way to do the count.
It also converts of_gpio_named_count() to use the new function instead
of using the above described horrible method.
This also requires the return value of of_gpio_count() &
of_gpio_named_count() from 'unsigned int' to 'int' so that it can return
an error code. All the users of that function are fixed up to correctly
handle a negative return value.
Tested on ARM using the selftest code.
v2: - fix bug where of_parse_phandle_with_args() could behave like _count_.
- made of_gpio_named_count() into a static inline regardless of CONFIG_OF_GPIO
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Andreas Larsson <andreas@gaisler.com>
---
drivers/of/base.c | 56 ++++++++++++++++++++++++++++++++++++++++++-------
drivers/of/selftest.c | 25 ++++++++++++++++++++--
include/linux/of.h | 9 ++++++++
3 files changed, 80 insertions(+), 10 deletions(-)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index e2d44e0..adaa815 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1082,12 +1082,13 @@ EXPORT_SYMBOL(of_parse_phandle);
* To get a device_node of the `node2' node you may call this:
* of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
*/
-int of_parse_phandle_with_args(const struct device_node *np, const char *list_name,
- const char *cells_name, int index,
- struct of_phandle_args *out_args)
+static int __of_parse_phandle_with_args(const struct device_node *np,
+ const char *list_name,
+ const char *cells_name, int index,
+ struct of_phandle_args *out_args)
{
const __be32 *list, *list_end;
- int size, cur_index = 0;
+ int rc = 0, size, cur_index = 0;
uint32_t count = 0;
struct device_node *node = NULL;
phandle phandle;
@@ -1116,12 +1117,14 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na
if (!node) {
pr_err("%s: could not find phandle\n",
np->full_name);
+ rc = -EINVAL;
break;
}
if (of_property_read_u32(node, cells_name, &count)) {
pr_err("%s: could not get %s for %s\n",
np->full_name, cells_name,
node->full_name);
+ rc = -EINVAL;
break;
}
@@ -1132,6 +1135,7 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na
if (list + count > list_end) {
pr_err("%s: arguments longer than property\n",
np->full_name);
+ rc = -EINVAL;
break;
}
}
@@ -1143,8 +1147,10 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na
* or return -ENOENT for an empty entry.
*/
if (cur_index == index) {
- if (!phandle)
- return -ENOENT;
+ if (!phandle) {
+ rc = -ENOENT;
+ break;
+ }
if (out_args) {
int i;
@@ -1155,22 +1161,56 @@ int of_parse_phandle_with_args(const struct device_node *np, const char *list_na
for (i = 0; i < count; i++)
out_args->args[i] = be32_to_cpup(list++);
}
- return 0;
+
+ rc = 0;
+ break;
}
of_node_put(node);
node = NULL;
list += count;
cur_index++;
+ rc = cur_index;
}
/* Loop exited without finding a valid entry; return an error */
if (node)
of_node_put(node);
- return -EINVAL;
+ return index < 0 ? rc : -ENOENT;
+}
+
+int of_parse_phandle_with_args(const struct device_node *np, const char *list_name,
+ const char *cells_name, int index,
+ struct of_phandle_args *out_args)
+{
+ if (index < 0)
+ return -EINVAL;
+ return __of_parse_phandle_with_args(np, list_name, cells_name, index, out_args);
}
EXPORT_SYMBOL(of_parse_phandle_with_args);
+/**
+ * of_count_phandle_with_args() - Find the number of phandles references in a property
+ * @np: pointer to a device tree node containing a list
+ * @list_name: property name that contains a list
+ * @cells_name: property name that specifies phandles' arguments count
+ *
+ * Returns the number of phandle + argument tuples within a property. It
+ * is a typical pattern to encode a list of phandle and variable
+ * arguments into a single property. The number of arguments is encoded
+ * by a property in the phandle-target node. For example, a gpios
+ * property would contain a list of GPIO specifies consisting of a
+ * phandle and 1 or more arguments. The number of arguments are
+ * determined by the #gpio-cells property in the node pointed to by the
+ * phandle.
+ */
+int of_count_phandle_with_args(const struct device_node *np, const char *list_name,
+ const char *cells_name)
+{
+ return __of_parse_phandle_with_args(np, list_name, cells_name, -1, NULL);
+}
+EXPORT_SYMBOL(of_count_phandle_with_args);
+
#if defined(CONFIG_OF_DYNAMIC)
static int of_property_notify(int action, struct device_node *np,
struct property *prop)
diff --git a/drivers/of/selftest.c b/drivers/of/selftest.c
index 9f62eb5..9c44491 100644
--- a/drivers/of/selftest.c
+++ b/drivers/of/selftest.c
@@ -35,6 +35,11 @@ static void __init of_selftest_parse_phandle_with_args(void)
return;
}
+ rc = of_count_phandle_with_args(np, "phandle-list", "#phandle-cells");
+ if (rc != 7)
+ pr_err("of_count_phandle_with_args() returned %i, expected 7\n", rc);
+ passed_all &= (rc == 7);
+
for (i = 0; i < 8; i++) {
bool passed = true;
rc = of_parse_phandle_with_args(np, "phandle-list",
@@ -79,7 +84,7 @@ static void __init of_selftest_parse_phandle_with_args(void)
passed &= (args.args[0] == (i + 1));
break;
case 7:
- passed &= (rc == -EINVAL);
+ passed &= (rc == -ENOENT);
break;
default:
passed = false;
@@ -100,22 +105,38 @@ static void __init of_selftest_parse_phandle_with_args(void)
/* Check for missing list property */
rc = of_parse_phandle_with_args(np, "phandle-list-missing",
"#phandle-cells", 0, &args);
- passed_all &= (rc == -EINVAL);
+ passed_all &= (rc == -ENOENT);
+ rc = of_count_phandle_with_args(np, "phandle-list-missing",
+ "#phandle-cells");
+ passed_all &= (rc == -ENOENT);
+ pr_err("rc = %i\n", rc);
/* Check for missing cells property */
rc = of_parse_phandle_with_args(np, "phandle-list",
"#phandle-cells-missing", 0, &args);
passed_all &= (rc == -EINVAL);
+ rc = of_count_phandle_with_args(np, "phandle-list",
+ "#phandle-cells-missing");
+ passed_all &= (rc == -EINVAL);
+ pr_err("rc = %i\n", rc);
/* Check for bad phandle in list */
rc = of_parse_phandle_with_args(np, "phandle-list-bad-phandle",
"#phandle-cells", 0, &args);
passed_all &= (rc == -EINVAL);
+ rc = of_count_phandle_with_args(np, "phandle-list-bad-phandle",
+ "#phandle-cells");
+ passed_all &= (rc == -EINVAL);
+ pr_err("rc = %i\n", rc);
/* Check for incorrectly formed argument list */
rc = of_parse_phandle_with_args(np, "phandle-list-bad-args",
"#phandle-cells", 1, &args);
passed_all &= (rc == -EINVAL);
+ rc = of_count_phandle_with_args(np, "phandle-list-bad-args",
+ "#phandle-cells");
+ passed_all &= (rc == -EINVAL);
+ pr_err("rc = %i\n", rc);
pr_info("end - %s\n", passed_all ? "PASS" : "FAIL");
}
diff --git a/include/linux/of.h b/include/linux/of.h
index b9e1b91..f8a088c 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -277,6 +277,8 @@ extern struct device_node *of_parse_phandle(const struct device_node *np,
extern int of_parse_phandle_with_args(const struct device_node *np,
const char *list_name, const char *cells_name, int index,
struct of_phandle_args *out_args);
+extern int of_count_phandle_with_args(const struct device_node *np,
+ const char *list_name, const char *cells_name);
extern void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align));
extern int of_alias_get_id(struct device_node *np, const char *stem);
@@ -467,6 +469,13 @@ static inline int of_parse_phandle_with_args(struct device_node *np,
return -ENOSYS;
}
+static inline int of_parse_count_with_args(struct device_node *np,
+ const char *list_name,
+ const char *cells_name)
+{
+ return -ENOSYS;
+}
+
static inline int of_alias_get_id(struct device_node *np, const char *stem)
{
return -ENOSYS;
--
1.7.10.4
^ permalink raw reply [flat|nested] 3+ messages in thread* [PATCH V2 3/3] gpio: Make of_count_named_gpios() use new of_count_phandle_with_args()
2013-02-12 17:59 [PATCH V2 1/3] of/selftest: Fix GPIOs selftest to cover the 7th case Grant Likely
2013-02-12 17:59 ` [PATCH V2 2/3] of: Create function for counting number of phandles in a property Grant Likely
@ 2013-02-12 17:59 ` Grant Likely
1 sibling, 0 replies; 3+ messages in thread
From: Grant Likely @ 2013-02-12 17:59 UTC (permalink / raw)
To: linux-kernel, devicetree-discuss
Cc: Grant Likely, Linus Walleij, Rob Herring, Andreas Larsson
This patch replaces the horribly coded of_count_named_gpios() with a
call to of_count_phandle_with_args() which is far more efficient. This
also changes the return value of of_gpio_count() & of_gpio_named_count()
from 'unsigned int' to 'int' so that it can return an error code. All
the users of that function are fixed up to correctly handle a negative
return value.
v2: Split GPIO portion into a separate patch
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Andreas Larsson <andreas@gaisler.com>
---
drivers/gpio/gpiolib-of.c | 35 ----------------------------
drivers/hwmon/gpio-fan.c | 4 ++--
drivers/input/keyboard/matrix_keypad.c | 8 +++----
drivers/net/phy/mdio-mux-gpio.c | 4 ++--
drivers/spi/spi-fsl-spi.c | 4 ++--
drivers/spi/spi-oc-tiny.c | 8 +++----
drivers/spi/spi-ppc4xx.c | 4 ++--
drivers/spi/spi.c | 5 ++--
include/linux/of_gpio.h | 40 ++++++++++++++++++--------------
9 files changed, 41 insertions(+), 71 deletions(-)
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index d542a14..dd8a212 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -89,41 +89,6 @@ int of_get_named_gpio_flags(struct device_node *np, const char *propname,
EXPORT_SYMBOL(of_get_named_gpio_flags);
/**
- * of_gpio_named_count - Count GPIOs for a device
- * @np: device node to count GPIOs for
- * @propname: property name containing gpio specifier(s)
- *
- * The function returns the count of GPIOs specified for a node.
- *
- * Note that the empty GPIO specifiers counts too. For example,
- *
- * gpios = <0
- * &pio1 1 2
- * 0
- * &pio2 3 4>;
- *
- * defines four GPIOs (so this function will return 4), two of which
- * are not specified.
- */
-unsigned int of_gpio_named_count(struct device_node *np, const char* propname)
-{
- unsigned int cnt = 0;
-
- do {
- int ret;
-
- ret = of_parse_phandle_with_args(np, propname, "#gpio-cells",
- cnt, NULL);
- /* A hole in the gpios = <> counts anyway. */
- if (ret < 0 && ret != -EEXIST)
- break;
- } while (++cnt);
-
- return cnt;
-}
-EXPORT_SYMBOL(of_gpio_named_count);
-
-/**
* of_gpio_simple_xlate - translate gpio_spec to the GPIO number and flags
* @gc: pointer to the gpio_chip structure
* @np: device node of the GPIO chip
diff --git a/drivers/hwmon/gpio-fan.c b/drivers/hwmon/gpio-fan.c
index 4e04c12..3978194 100644
--- a/drivers/hwmon/gpio-fan.c
+++ b/drivers/hwmon/gpio-fan.c
@@ -422,7 +422,7 @@ static int gpio_fan_get_of_pdata(struct device *dev,
/* Fill GPIO pin array */
pdata->num_ctrl = of_gpio_count(node);
- if (!pdata->num_ctrl) {
+ if (pdata->num_ctrl <= 0) {
dev_err(dev, "gpios DT property empty / missing");
return -ENODEV;
}
@@ -477,7 +477,7 @@ static int gpio_fan_get_of_pdata(struct device *dev,
pdata->speed = speed;
/* Alarm GPIO if one exists */
- if (of_gpio_named_count(node, "alarm-gpios")) {
+ if (of_gpio_named_count(node, "alarm-gpios") > 0) {
struct gpio_fan_alarm *alarm;
int val;
enum of_gpio_flags flags;
diff --git a/drivers/input/keyboard/matrix_keypad.c b/drivers/input/keyboard/matrix_keypad.c
index f4ff0dd..71d7719 100644
--- a/drivers/input/keyboard/matrix_keypad.c
+++ b/drivers/input/keyboard/matrix_keypad.c
@@ -403,7 +403,7 @@ matrix_keypad_parse_dt(struct device *dev)
struct matrix_keypad_platform_data *pdata;
struct device_node *np = dev->of_node;
unsigned int *gpios;
- int i;
+ int i, nrow, ncol;
if (!np) {
dev_err(dev, "device lacks DT data\n");
@@ -416,9 +416,9 @@ matrix_keypad_parse_dt(struct device *dev)
return ERR_PTR(-ENOMEM);
}
- pdata->num_row_gpios = of_gpio_named_count(np, "row-gpios");
- pdata->num_col_gpios = of_gpio_named_count(np, "col-gpios");
- if (!pdata->num_row_gpios || !pdata->num_col_gpios) {
+ pdata->num_row_gpios = nrow = of_gpio_named_count(np, "row-gpios");
+ pdata->num_col_gpios = ncol = of_gpio_named_count(np, "col-gpios");
+ if (nrow <= 0 || ncol <= 0) {
dev_err(dev, "number of keypad rows/columns not specified\n");
return ERR_PTR(-EINVAL);
}
diff --git a/drivers/net/phy/mdio-mux-gpio.c b/drivers/net/phy/mdio-mux-gpio.c
index 0c9accb..e91d7d7 100644
--- a/drivers/net/phy/mdio-mux-gpio.c
+++ b/drivers/net/phy/mdio-mux-gpio.c
@@ -53,7 +53,7 @@ static int mdio_mux_gpio_probe(struct platform_device *pdev)
{
enum of_gpio_flags f;
struct mdio_mux_gpio_state *s;
- unsigned int num_gpios;
+ int num_gpios;
unsigned int n;
int r;
@@ -61,7 +61,7 @@ static int mdio_mux_gpio_probe(struct platform_device *pdev)
return -ENODEV;
num_gpios = of_gpio_count(pdev->dev.of_node);
- if (num_gpios == 0 || num_gpios > MDIO_MUX_GPIO_MAX_BITS)
+ if (num_gpios <= 0 || num_gpios > MDIO_MUX_GPIO_MAX_BITS)
return -ENODEV;
s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c
index 1a7f635..086a9ee 100644
--- a/drivers/spi/spi-fsl-spi.c
+++ b/drivers/spi/spi-fsl-spi.c
@@ -947,12 +947,12 @@ static int of_fsl_spi_get_chipselects(struct device *dev)
struct device_node *np = dev->of_node;
struct fsl_spi_platform_data *pdata = dev->platform_data;
struct mpc8xxx_spi_probe_info *pinfo = to_of_pinfo(pdata);
- unsigned int ngpios;
+ int ngpios;
int i = 0;
int ret;
ngpios = of_gpio_count(np);
- if (!ngpios) {
+ if (ngpios <= 0) {
/*
* SPI w/o chip-select line. One SPI device is still permitted
* though.
diff --git a/drivers/spi/spi-oc-tiny.c b/drivers/spi/spi-oc-tiny.c
index 432e66e..cb2e284 100644
--- a/drivers/spi/spi-oc-tiny.c
+++ b/drivers/spi/spi-oc-tiny.c
@@ -54,7 +54,7 @@ struct tiny_spi {
unsigned int txc, rxc;
const u8 *txp;
u8 *rxp;
- unsigned int gpio_cs_count;
+ int gpio_cs_count;
int *gpio_cs;
};
@@ -74,7 +74,7 @@ static void tiny_spi_chipselect(struct spi_device *spi, int is_active)
{
struct tiny_spi *hw = tiny_spi_to_hw(spi);
- if (hw->gpio_cs_count) {
+ if (hw->gpio_cs_count > 0) {
gpio_set_value(hw->gpio_cs[spi->chip_select],
(spi->mode & SPI_CS_HIGH) ? is_active : !is_active);
}
@@ -254,7 +254,7 @@ static int tiny_spi_of_probe(struct platform_device *pdev)
if (!np)
return 0;
hw->gpio_cs_count = of_gpio_count(np);
- if (hw->gpio_cs_count) {
+ if (hw->gpio_cs_count > 0) {
hw->gpio_cs = devm_kzalloc(&pdev->dev,
hw->gpio_cs_count * sizeof(unsigned int),
GFP_KERNEL);
@@ -352,7 +352,7 @@ static int tiny_spi_probe(struct platform_device *pdev)
goto exit_gpio;
gpio_direction_output(hw->gpio_cs[i], 1);
}
- hw->bitbang.master->num_chipselect = max(1U, hw->gpio_cs_count);
+ hw->bitbang.master->num_chipselect = max(1, hw->gpio_cs_count);
/* register our spi controller */
err = spi_bitbang_start(&hw->bitbang);
diff --git a/drivers/spi/spi-ppc4xx.c b/drivers/spi/spi-ppc4xx.c
index 7a85f22..af3e6e7 100644
--- a/drivers/spi/spi-ppc4xx.c
+++ b/drivers/spi/spi-ppc4xx.c
@@ -419,7 +419,7 @@ static int __init spi_ppc4xx_of_probe(struct platform_device *op)
* This includes both "null" gpio's and real ones.
*/
num_gpios = of_gpio_count(np);
- if (num_gpios) {
+ if (num_gpios > 0) {
int i;
hw->gpios = kzalloc(sizeof(int) * num_gpios, GFP_KERNEL);
@@ -471,7 +471,7 @@ static int __init spi_ppc4xx_of_probe(struct platform_device *op)
SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | SPI_LSB_FIRST;
/* this many pins in all GPIO controllers */
- bbp->master->num_chipselect = num_gpios;
+ bbp->master->num_chipselect = num_gpios > 0 ? num_gpios : 0;
/* Get the clock for the OPB */
opbnp = of_find_compatible_node(NULL, NULL, "ibm,opb");
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 19ee901..21c4748 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1059,15 +1059,14 @@ EXPORT_SYMBOL_GPL(spi_alloc_master);
#ifdef CONFIG_OF
static int of_spi_register_master(struct spi_master *master)
{
- u16 nb;
- int i, *cs;
+ int nb, i, *cs;
struct device_node *np = master->dev.of_node;
if (!np)
return 0;
nb = of_gpio_named_count(np, "cs-gpios");
- master->num_chipselect = max(nb, master->num_chipselect);
+ master->num_chipselect = max(nb, (int)master->num_chipselect);
if (nb < 1)
return 0;
diff --git a/include/linux/of_gpio.h b/include/linux/of_gpio.h
index c454f57..a83dc6f 100644
--- a/include/linux/of_gpio.h
+++ b/include/linux/of_gpio.h
@@ -50,9 +50,6 @@ static inline struct of_mm_gpio_chip *to_of_mm_gpio_chip(struct gpio_chip *gc)
extern int of_get_named_gpio_flags(struct device_node *np,
const char *list_name, int index, enum of_gpio_flags *flags);
-extern unsigned int of_gpio_named_count(struct device_node *np,
- const char* propname);
-
extern int of_mm_gpiochip_add(struct device_node *np,
struct of_mm_gpio_chip *mm_gc);
@@ -71,12 +68,6 @@ static inline int of_get_named_gpio_flags(struct device_node *np,
return -ENOSYS;
}
-static inline unsigned int of_gpio_named_count(struct device_node *np,
- const char* propname)
-{
- return 0;
-}
-
static inline int of_gpio_simple_xlate(struct gpio_chip *gc,
const struct of_phandle_args *gpiospec,
u32 *flags)
@@ -90,22 +81,37 @@ static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
#endif /* CONFIG_OF_GPIO */
/**
- * of_gpio_count - Count GPIOs for a device
+ * of_gpio_named_count() - Count GPIOs for a device
* @np: device node to count GPIOs for
+ * @propname: property name containing gpio specifier(s)
*
* The function returns the count of GPIOs specified for a node.
+ * Note that the empty GPIO specifiers count too. Returns either
+ * Number of gpios defined in property,
+ * -EINVAL for an incorrectly formed gpios property, or
+ * -ENOENT for a missing gpios property
*
- * Note that the empty GPIO specifiers counts too. For example,
- *
+ * Example:
* gpios = <0
- * &pio1 1 2
+ * &gpio1 1 2
* 0
- * &pio2 3 4>;
+ * &gpio2 3 4>;
+ *
+ * The above example defines four GPIOs, two of which are not specified.
+ * This function will return '4'
+ */
+static inline int of_gpio_named_count(struct device_node *np, const char* propname)
+{
+ return of_count_phandle_with_args(np, propname, "#gpio-cells");
+}
+
+/**
+ * of_gpio_count() - Count GPIOs for a device
+ * @np: device node to count GPIOs for
*
- * defines four GPIOs (so this function will return 4), two of which
- * are not specified.
+ * Same as of_gpio_named_count, but hard coded to use the 'gpios' property
*/
-static inline unsigned int of_gpio_count(struct device_node *np)
+static inline int of_gpio_count(struct device_node *np)
{
return of_gpio_named_count(np, "gpios");
}
--
1.7.10.4
^ permalink raw reply [flat|nested] 3+ messages in thread