This patch set introduces ACPI support for PN544.
gpio_set_value was replaced with gpio_set_value_cansleep in order
to allow GPIO access that may sleep. This is particularelly useful
when GPIO is accessed using busses like I2C, SPI, USB
Changes since v1:
- Added cover letter
- Removed debug define and Kconfig include
- Minor fixes to patch subjects
Links to v1:
- http://lkml.iu.edu/hypermail/linux/kernel/1501.1/00943.html
- http://lkml.iu.edu/hypermail/linux/kernel/1501.1/00944.html
Robert Dolca (2):
NFC: PN544: GPIO access that may sleep
NFC: Add ACPI support for NXP PN544
drivers/nfc/pn544/i2c.c | 137 +++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 124 insertions(+), 13 deletions(-)
--
1.9.1
Hi Robert,
On Mon, Jan 26, 2015 at 01:13:35PM +0200, Robert Dolca wrote:
> This patch set introduces ACPI support for PN544.
>
> gpio_set_value was replaced with gpio_set_value_cansleep in order
> to allow GPIO access that may sleep. This is particularelly useful
> when GPIO is accessed using busses like I2C, SPI, USB
>
> Changes since v1:
> - Added cover letter
> - Removed debug define and Kconfig include
> - Minor fixes to patch subjects
>
> Links to v1:
> - http://lkml.iu.edu/hypermail/linux/kernel/1501.1/00943.html
> - http://lkml.iu.edu/hypermail/linux/kernel/1501.1/00944.html
>
> Robert Dolca (2):
> NFC: PN544: GPIO access that may sleep
> NFC: Add ACPI support for NXP PN544
Both patches applied, many thanks.
Cheers,
Samuel.
gpio_set_value was replaced with gpio_set_value_cansleep in order
to allow GPIO access that may sleep. This is particularelly useful
when GPIO is accessed using busses like I2C, SPI, USB
Signed-off-by: Robert Dolca <[email protected]>
---
drivers/nfc/pn544/i2c.c | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)
diff --git a/drivers/nfc/pn544/i2c.c b/drivers/nfc/pn544/i2c.c
index fc02e8d..d9018cd 100644
--- a/drivers/nfc/pn544/i2c.c
+++ b/drivers/nfc/pn544/i2c.c
@@ -195,18 +195,19 @@ static void pn544_hci_i2c_platform_init(struct pn544_i2c_phy *phy)
nfc_info(&phy->i2c_dev->dev, "Detecting nfc_en polarity\n");
/* Disable fw download */
- gpio_set_value(phy->gpio_fw, 0);
+ gpio_set_value_cansleep(phy->gpio_fw, 0);
for (polarity = 0; polarity < 2; polarity++) {
phy->en_polarity = polarity;
retry = 3;
while (retry--) {
/* power off */
- gpio_set_value(phy->gpio_en, !phy->en_polarity);
+ gpio_set_value_cansleep(phy->gpio_en,
+ !phy->en_polarity);
usleep_range(10000, 15000);
/* power on */
- gpio_set_value(phy->gpio_en, phy->en_polarity);
+ gpio_set_value_cansleep(phy->gpio_en, phy->en_polarity);
usleep_range(10000, 15000);
/* send reset */
@@ -225,13 +226,14 @@ static void pn544_hci_i2c_platform_init(struct pn544_i2c_phy *phy)
"Could not detect nfc_en polarity, fallback to active high\n");
out:
- gpio_set_value(phy->gpio_en, !phy->en_polarity);
+ gpio_set_value_cansleep(phy->gpio_en, !phy->en_polarity);
}
static void pn544_hci_i2c_enable_mode(struct pn544_i2c_phy *phy, int run_mode)
{
- gpio_set_value(phy->gpio_fw, run_mode == PN544_FW_MODE ? 1 : 0);
- gpio_set_value(phy->gpio_en, phy->en_polarity);
+ gpio_set_value_cansleep(phy->gpio_fw,
+ run_mode == PN544_FW_MODE ? 1 : 0);
+ gpio_set_value_cansleep(phy->gpio_en, phy->en_polarity);
usleep_range(10000, 15000);
phy->run_mode = run_mode;
@@ -254,14 +256,14 @@ static void pn544_hci_i2c_disable(void *phy_id)
{
struct pn544_i2c_phy *phy = phy_id;
- gpio_set_value(phy->gpio_fw, 0);
- gpio_set_value(phy->gpio_en, !phy->en_polarity);
+ gpio_set_value_cansleep(phy->gpio_fw, 0);
+ gpio_set_value_cansleep(phy->gpio_en, !phy->en_polarity);
usleep_range(10000, 15000);
- gpio_set_value(phy->gpio_en, phy->en_polarity);
+ gpio_set_value_cansleep(phy->gpio_en, phy->en_polarity);
usleep_range(10000, 15000);
- gpio_set_value(phy->gpio_en, !phy->en_polarity);
+ gpio_set_value_cansleep(phy->gpio_en, !phy->en_polarity);
usleep_range(10000, 15000);
phy->powered = 0;
--
1.9.1
Hi Robert,
On Mon, Jan 26, 2015 at 01:13:37PM +0200, Robert Dolca wrote:
> @@ -1022,9 +1127,12 @@ static int pn544_hci_i2c_probe(struct i2c_client *client,
> PN544_I2C_FRAME_HEADROOM, PN544_I2C_FRAME_TAILROOM,
> PN544_HCI_I2C_LLC_MAX_PAYLOAD,
> pn544_hci_i2c_fw_download, &phy->hdev);
> - if (r < 0)
> + if (r < 0) {
> + nfc_err(&client->dev, "HCI Probing error\n");
> goto err_hci;
> + }
>
> + nfc_info(&client->dev, "NFC I2C driver loaded\n");
> return 0;
This is unrelated to this patch, so I removed that part.
Cheers,
Samuel.
Currently there is no support for ACPI.
This patch uses the following configuration:
- Device id: NXP5440
- Pin mapping:
- 0 IRQ pin
- 1 enable pin
- 2 firmware pin
Signed-off-by: Robert Dolca <[email protected]>
---
drivers/nfc/pn544/i2c.c | 115 ++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 112 insertions(+), 3 deletions(-)
diff --git a/drivers/nfc/pn544/i2c.c b/drivers/nfc/pn544/i2c.c
index d9018cd..ae817b0 100644
--- a/drivers/nfc/pn544/i2c.c
+++ b/drivers/nfc/pn544/i2c.c
@@ -24,6 +24,7 @@
#include <linux/gpio.h>
#include <linux/of_gpio.h>
#include <linux/of_irq.h>
+#include <linux/acpi.h>
#include <linux/miscdevice.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
@@ -41,6 +42,11 @@
#define PN544_I2C_FRAME_HEADROOM 1
#define PN544_I2C_FRAME_TAILROOM 2
+/* GPIO names */
+#define PN544_GPIO_NAME_IRQ "pn544_irq"
+#define PN544_GPIO_NAME_FW "pn544_fw"
+#define PN544_GPIO_NAME_EN "pn544_en"
+
/* framing in HCI mode */
#define PN544_HCI_I2C_LLC_LEN 1
#define PN544_HCI_I2C_LLC_CRC 2
@@ -58,6 +64,13 @@ static struct i2c_device_id pn544_hci_i2c_id_table[] = {
MODULE_DEVICE_TABLE(i2c, pn544_hci_i2c_id_table);
+static const struct acpi_device_id pn544_hci_i2c_acpi_match[] = {
+ {"NXP5440", 0},
+ {}
+};
+
+MODULE_DEVICE_TABLE(acpi, pn544_hci_i2c_acpi_match);
+
#define PN544_HCI_I2C_DRIVER_NAME "pn544_hci_i2c"
/*
@@ -861,6 +874,90 @@ exit_state_wait_secure_write_answer:
}
}
+static int pn544_hci_i2c_acpi_request_resources(struct i2c_client *client)
+{
+ struct pn544_i2c_phy *phy = i2c_get_clientdata(client);
+ const struct acpi_device_id *id;
+ struct gpio_desc *gpiod_en, *gpiod_irq, *gpiod_fw;
+ struct device *dev;
+ int ret;
+
+ if (!client)
+ return -EINVAL;
+
+ dev = &client->dev;
+
+ /* Match the struct device against a given list of ACPI IDs */
+ id = acpi_match_device(dev->driver->acpi_match_table, dev);
+
+ if (!id)
+ return -ENODEV;
+
+ /* Get EN GPIO from ACPI */
+ gpiod_en = devm_gpiod_get_index(dev, PN544_GPIO_NAME_EN, 1);
+ if (IS_ERR(gpiod_en)) {
+ nfc_err(dev,
+ "Unable to get EN GPIO\n");
+ return -ENODEV;
+ }
+
+ phy->gpio_en = desc_to_gpio(gpiod_en);
+
+ /* Configuration EN GPIO */
+ ret = gpiod_direction_output(gpiod_en, 0);
+ if (ret) {
+ nfc_err(dev, "Fail EN pin direction\n");
+ return ret;
+ }
+
+ /* Get FW GPIO from ACPI */
+ gpiod_fw = devm_gpiod_get_index(dev, PN544_GPIO_NAME_FW, 2);
+ if (IS_ERR(gpiod_fw)) {
+ nfc_err(dev,
+ "Unable to get FW GPIO\n");
+ return -ENODEV;
+ }
+
+ phy->gpio_fw = desc_to_gpio(gpiod_fw);
+
+ /* Configuration FW GPIO */
+ ret = gpiod_direction_output(gpiod_fw, 0);
+ if (ret) {
+ nfc_err(dev, "Fail FW pin direction\n");
+ return ret;
+ }
+
+ /* Get IRQ GPIO */
+ gpiod_irq = devm_gpiod_get_index(dev, PN544_GPIO_NAME_IRQ, 0);
+ if (IS_ERR(gpiod_irq)) {
+ nfc_err(dev,
+ "Unable to get IRQ GPIO\n");
+ return -ENODEV;
+ }
+
+ phy->gpio_irq = desc_to_gpio(gpiod_irq);
+
+ /* Configure IRQ GPIO */
+ ret = gpiod_direction_input(gpiod_irq);
+ if (ret) {
+ nfc_err(dev, "Fail IRQ pin direction\n");
+ return ret;
+ }
+
+ /* Map the pin to an IRQ */
+ ret = gpiod_to_irq(gpiod_irq);
+ if (ret < 0) {
+ nfc_err(dev, "Fail pin IRQ mapping\n");
+ return ret;
+ }
+
+ nfc_info(dev, "GPIO resource, no:%d irq:%d\n",
+ desc_to_gpio(gpiod_irq), ret);
+ client->irq = ret;
+
+ return 0;
+}
+
#ifdef CONFIG_OF
static int pn544_hci_i2c_of_request_resources(struct i2c_client *client)
@@ -886,7 +983,7 @@ static int pn544_hci_i2c_of_request_resources(struct i2c_client *client)
phy->gpio_en = ret;
/* Configuration of EN GPIO */
- ret = gpio_request(phy->gpio_en, "pn544_en");
+ ret = gpio_request(phy->gpio_en, PN544_GPIO_NAME_EN);
if (ret) {
nfc_err(&client->dev, "Fail EN pin\n");
goto err_dt;
@@ -908,7 +1005,7 @@ static int pn544_hci_i2c_of_request_resources(struct i2c_client *client)
phy->gpio_fw = ret;
/* Configuration of FW GPIO */
- ret = gpio_request(phy->gpio_fw, "pn544_fw");
+ ret = gpio_request(phy->gpio_fw, PN544_GPIO_NAME_FW);
if (ret) {
nfc_err(&client->dev, "Fail FW pin\n");
goto err_gpio_en;
@@ -1003,6 +1100,14 @@ static int pn544_hci_i2c_probe(struct i2c_client *client,
phy->gpio_en = pdata->get_gpio(NFC_GPIO_ENABLE);
phy->gpio_fw = pdata->get_gpio(NFC_GPIO_FW_RESET);
phy->gpio_irq = pdata->get_gpio(NFC_GPIO_IRQ);
+ /* Using ACPI */
+ } else if (ACPI_HANDLE(&client->dev)) {
+ r = pn544_hci_i2c_acpi_request_resources(client);
+ if (r) {
+ nfc_err(&client->dev,
+ "Cannot get ACPI data\n");
+ return r;
+ }
} else {
nfc_err(&client->dev, "No platform data\n");
return -EINVAL;
@@ -1022,9 +1127,12 @@ static int pn544_hci_i2c_probe(struct i2c_client *client,
PN544_I2C_FRAME_HEADROOM, PN544_I2C_FRAME_TAILROOM,
PN544_HCI_I2C_LLC_MAX_PAYLOAD,
pn544_hci_i2c_fw_download, &phy->hdev);
- if (r < 0)
+ if (r < 0) {
+ nfc_err(&client->dev, "HCI Probing error\n");
goto err_hci;
+ }
+ nfc_info(&client->dev, "NFC I2C driver loaded\n");
return 0;
err_hci:
@@ -1082,6 +1190,7 @@ static struct i2c_driver pn544_hci_i2c_driver = {
.name = PN544_HCI_I2C_DRIVER_NAME,
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(of_pn544_i2c_match),
+ .acpi_match_table = ACPI_PTR(pn544_hci_i2c_acpi_match),
},
.probe = pn544_hci_i2c_probe,
.id_table = pn544_hci_i2c_id_table,
--
1.9.1
Hello,
On Mon, Jan 26, 2015 at 01:13:37PM +0200, Robert Dolca wrote:
> + /* Get EN GPIO from ACPI */
> + gpiod_en = devm_gpiod_get_index(dev, PN544_GPIO_NAME_EN, 1);
Actually devm_gpiod_get_index takes 4 arguments. In your case you should
also pass GPIOD_OUT_LOW, then you can skip the gpiod_direction_output
part below.
> + if (IS_ERR(gpiod_en)) {
> + nfc_err(dev,
> + "Unable to get EN GPIO\n");
> + return -ENODEV;
> + }
> +
> + phy->gpio_en = desc_to_gpio(gpiod_en);
Why don't you save a reference to the gpiod instead? Mixing usage of raw
and gpiod might result in surprising results. For example
gpiod_direction_output(gpiod_en, 0);
might actually have the same result as
gpio_direction_output(gpio_en, 1);
if the matching gpio is marked as active low.
> +
> + /* Configuration EN GPIO */
> + ret = gpiod_direction_output(gpiod_en, 0);
> + if (ret) {
> + nfc_err(dev, "Fail EN pin direction\n");
> + return ret;
> + }
> +
> + /* Get FW GPIO from ACPI */
> + gpiod_fw = devm_gpiod_get_index(dev, PN544_GPIO_NAME_FW, 2);
> + if (IS_ERR(gpiod_fw)) {
> + nfc_err(dev,
> + "Unable to get FW GPIO\n");
> + return -ENODEV;
> + }
> +
> + phy->gpio_fw = desc_to_gpio(gpiod_fw);
> +
> + /* Configuration FW GPIO */
> + ret = gpiod_direction_output(gpiod_fw, 0);
> + if (ret) {
> + nfc_err(dev, "Fail FW pin direction\n");
> + return ret;
> + }
The same comments apply here.
> +
> + /* Get IRQ GPIO */
> + gpiod_irq = devm_gpiod_get_index(dev, PN544_GPIO_NAME_IRQ, 0);
> + if (IS_ERR(gpiod_irq)) {
> + nfc_err(dev,
> + "Unable to get IRQ GPIO\n");
> + return -ENODEV;
> + }
> +
> + phy->gpio_irq = desc_to_gpio(gpiod_irq);
> +
> + /* Configure IRQ GPIO */
> + ret = gpiod_direction_input(gpiod_irq);
> + if (ret) {
> + nfc_err(dev, "Fail IRQ pin direction\n");
> + return ret;
> + }
> +
> + /* Map the pin to an IRQ */
> + ret = gpiod_to_irq(gpiod_irq);
> + if (ret < 0) {
> + nfc_err(dev, "Fail pin IRQ mapping\n");
> + return ret;
> + }
and here.
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | http://www.pengutronix.de/ |
Hi Uwe,
On Thu, Feb 12, 2015 at 09:14:59AM +0100, Uwe Kleine-K?nig wrote:
> On Mon, Jan 26, 2015 at 01:13:37PM +0200, Robert Dolca wrote:
> > + /* Get EN GPIO from ACPI */
> > + gpiod_en = devm_gpiod_get_index(dev, PN544_GPIO_NAME_EN, 1);
> Actually devm_gpiod_get_index takes 4 arguments. In your case you should
> also pass GPIOD_OUT_LOW, then you can skip the gpiod_direction_output
> part below.
>
> > + if (IS_ERR(gpiod_en)) {
> > + nfc_err(dev,
> > + "Unable to get EN GPIO\n");
> > + return -ENODEV;
> > + }
> > +
> > + phy->gpio_en = desc_to_gpio(gpiod_en);
> Why don't you save a reference to the gpiod instead? Mixing usage of raw
> and gpiod might result in surprising results. For example
>
> gpiod_direction_output(gpiod_en, 0);
>
> might actually have the same result as
>
> gpio_direction_output(gpio_en, 1);
>
> if the matching gpio is marked as active low.
>
> > +
> > + /* Configuration EN GPIO */
> > + ret = gpiod_direction_output(gpiod_en, 0);
> > + if (ret) {
> > + nfc_err(dev, "Fail EN pin direction\n");
> > + return ret;
> > + }
> > +
> > + /* Get FW GPIO from ACPI */
> > + gpiod_fw = devm_gpiod_get_index(dev, PN544_GPIO_NAME_FW, 2);
> > + if (IS_ERR(gpiod_fw)) {
> > + nfc_err(dev,
> > + "Unable to get FW GPIO\n");
> > + return -ENODEV;
> > + }
> > +
> > + phy->gpio_fw = desc_to_gpio(gpiod_fw);
> > +
> > + /* Configuration FW GPIO */
> > + ret = gpiod_direction_output(gpiod_fw, 0);
> > + if (ret) {
> > + nfc_err(dev, "Fail FW pin direction\n");
> > + return ret;
> > + }
> The same comments apply here.
>
> > +
> > + /* Get IRQ GPIO */
> > + gpiod_irq = devm_gpiod_get_index(dev, PN544_GPIO_NAME_IRQ, 0);
> > + if (IS_ERR(gpiod_irq)) {
> > + nfc_err(dev,
> > + "Unable to get IRQ GPIO\n");
> > + return -ENODEV;
> > + }
> > +
> > + phy->gpio_irq = desc_to_gpio(gpiod_irq);
> > +
> > + /* Configure IRQ GPIO */
> > + ret = gpiod_direction_input(gpiod_irq);
> > + if (ret) {
> > + nfc_err(dev, "Fail IRQ pin direction\n");
> > + return ret;
> > + }
> > +
> > + /* Map the pin to an IRQ */
> > + ret = gpiod_to_irq(gpiod_irq);
> > + if (ret < 0) {
> > + nfc_err(dev, "Fail pin IRQ mapping\n");
> > + return ret;
> > + }
> and here.
I didn't use gpiod_* functions because the existing enumeration method for
platform init and device tree was using gpio_* functions.
Also as far as I know the device tree implementation will not give you the
gpiod data structure. It gives you only the gpio index.
Keeping both gpiod and gpio depending on the enumeration method is unscallable
so I didn't choose that.
Regards,
Robert
Hello Robert,
On Thu, Feb 12, 2015 at 07:48:43PM +0200, Robert Dolca wrote:
> On Thu, Feb 12, 2015 at 09:14:59AM +0100, Uwe Kleine-K?nig wrote:
> > On Mon, Jan 26, 2015 at 01:13:37PM +0200, Robert Dolca wrote:
> > > + /* Get EN GPIO from ACPI */
> > > + gpiod_en = devm_gpiod_get_index(dev, PN544_GPIO_NAME_EN, 1);
> > Actually devm_gpiod_get_index takes 4 arguments. In your case you should
> > also pass GPIOD_OUT_LOW, then you can skip the gpiod_direction_output
> > part below.
> >
> > > + if (IS_ERR(gpiod_en)) {
> > > + nfc_err(dev,
> > > + "Unable to get EN GPIO\n");
> > > + return -ENODEV;
> > > + }
> > > +
> > > + phy->gpio_en = desc_to_gpio(gpiod_en);
> > Why don't you save a reference to the gpiod instead? Mixing usage of raw
> > and gpiod might result in surprising results. For example
> >
> > gpiod_direction_output(gpiod_en, 0);
> >
> > might actually have the same result as
> >
> > gpio_direction_output(gpio_en, 1);
> >
> > if the matching gpio is marked as active low.
> >
> > > +
> > > + /* Configuration EN GPIO */
> > > + ret = gpiod_direction_output(gpiod_en, 0);
> > > + if (ret) {
> > > + nfc_err(dev, "Fail EN pin direction\n");
> > > + return ret;
> > > + }
> > > +
> > > + /* Get FW GPIO from ACPI */
> > > + gpiod_fw = devm_gpiod_get_index(dev, PN544_GPIO_NAME_FW, 2);
> > > + if (IS_ERR(gpiod_fw)) {
> > > + nfc_err(dev,
> > > + "Unable to get FW GPIO\n");
> > > + return -ENODEV;
> > > + }
> > > +
> > > + phy->gpio_fw = desc_to_gpio(gpiod_fw);
> > > +
> > > + /* Configuration FW GPIO */
> > > + ret = gpiod_direction_output(gpiod_fw, 0);
> > > + if (ret) {
> > > + nfc_err(dev, "Fail FW pin direction\n");
> > > + return ret;
> > > + }
> > The same comments apply here.
> >
> > > +
> > > + /* Get IRQ GPIO */
> > > + gpiod_irq = devm_gpiod_get_index(dev, PN544_GPIO_NAME_IRQ, 0);
> > > + if (IS_ERR(gpiod_irq)) {
> > > + nfc_err(dev,
> > > + "Unable to get IRQ GPIO\n");
> > > + return -ENODEV;
> > > + }
> > > +
> > > + phy->gpio_irq = desc_to_gpio(gpiod_irq);
> > > +
> > > + /* Configure IRQ GPIO */
> > > + ret = gpiod_direction_input(gpiod_irq);
> > > + if (ret) {
> > > + nfc_err(dev, "Fail IRQ pin direction\n");
> > > + return ret;
> > > + }
> > > +
> > > + /* Map the pin to an IRQ */
> > > + ret = gpiod_to_irq(gpiod_irq);
> > > + if (ret < 0) {
> > > + nfc_err(dev, "Fail pin IRQ mapping\n");
> > > + return ret;
> > > + }
> > and here.
> Also as far as I know the device tree implementation will not give you the
> gpiod data structure. It gives you only the gpio index.
What is "the device tree implementation"? If devm_gpiod_get_index gets
the information which gpio to use from a device tree that doesn't change
the return type, you still get a struct gpio_desc pointer. And it can
very well return a descriptor with GPIO_ACTIVE_LOW set, see the
implementation of of_find_gpio.
> Keeping both gpiod and gpio depending on the enumeration method is unscallable
> so I didn't choose that.
And if the descriptor has GPIO_ACTIVE_LOW set, you should better not
ignore it. The best thing to do here AFAIUI is to first convert the
driver to gpiod and then add your ACPI support in an additional patch.
And then please (this was the main motivation for my reply) your the
4-parameter version of devm_gpiod_get_index.
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | http://www.pengutronix.de/ |