[parent not found: <1449720055-25965-1-git-send-email-cory.tusar-J6Z/VSE8EyIAspv4Qr0y0gC/G2K4zDHf@public.gmane.org>]
* [PATCH v4 1/5] misc: eeprom_93xx46: Fix 16-bit read and write accesses.
[not found] ` <1449720055-25965-1-git-send-email-cory.tusar-J6Z/VSE8EyIAspv4Qr0y0gC/G2K4zDHf@public.gmane.org>
@ 2015-12-10 4:00 ` Cory Tusar
0 siblings, 0 replies; 14+ messages in thread
From: Cory Tusar @ 2015-12-10 4:00 UTC (permalink / raw)
To: robh+dt-DgEjT+Ai2ygdnm+yROfE0A, pawel.moll-5wv7dgnIgG8,
mark.rutland-5wv7dgnIgG8, ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg,
galak-sgV2jX0FEOL9JmXXK+q4OQ,
gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r
Cc: jic23-DgEjT+Ai2ygdnm+yROfE0A, vz-ChpfBGZJDbMAvxtiuMwx3w,
broonie-DgEjT+Ai2ygdnm+yROfE0A, afd-l0cyMroinI0,
andrew-g2DYL2Zd6BY, Chris.Healy-c8ZVq/bFV1I,
Keith.Vennel-c8ZVq/bFV1I, devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA, Cory Tusar
Compatible at93xx46 devices from both Microchip and Atmel expect a
word-based address, regardless of whether the device is strapped for 8-
or 16-bit operation. However, the offset parameter passed in when
reading or writing at a specific location is always specified in terms
of bytes.
This commit fixes 16-bit read and write accesses by shifting the offset
parameter to account for this difference between a byte offset and a
word-based address.
Signed-off-by: Cory Tusar <cory.tusar-J6Z/VSE8EyIAspv4Qr0y0gC/G2K4zDHf@public.gmane.org>
Tested-by: Chris Healy <chris.healy-c8ZVq/bFV1I@public.gmane.org>
---
drivers/misc/eeprom/eeprom_93xx46.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/misc/eeprom/eeprom_93xx46.c b/drivers/misc/eeprom/eeprom_93xx46.c
index ff63f05..e1bf0a5 100644
--- a/drivers/misc/eeprom/eeprom_93xx46.c
+++ b/drivers/misc/eeprom/eeprom_93xx46.c
@@ -54,7 +54,7 @@ eeprom_93xx46_bin_read(struct file *filp, struct kobject *kobj,
cmd_addr |= off & 0x7f;
bits = 10;
} else {
- cmd_addr |= off & 0x3f;
+ cmd_addr |= (off >> 1) & 0x3f;
bits = 9;
}
@@ -155,7 +155,7 @@ eeprom_93xx46_write_word(struct eeprom_93xx46_dev *edev,
bits = 10;
data_len = 1;
} else {
- cmd_addr |= off & 0x3f;
+ cmd_addr |= (off >> 1) & 0x3f;
bits = 9;
data_len = 2;
}
--
2.4.10
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
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More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply related [flat|nested] 14+ messages in thread
* [PATCH v4 2/5] Documentation: devicetree: Add DT bindings to eeprom_93xx46 driver.
2015-12-10 4:00 [PATCH v4 0/5] Devicetree support for misc/eeprom/eeprom_93xx46 Cory Tusar
[not found] ` <1449720055-25965-1-git-send-email-cory.tusar-J6Z/VSE8EyIAspv4Qr0y0gC/G2K4zDHf@public.gmane.org>
@ 2015-12-10 4:00 ` Cory Tusar
[not found] ` <1449720055-25965-3-git-send-email-cory.tusar-J6Z/VSE8EyIAspv4Qr0y0gC/G2K4zDHf@public.gmane.org>
2015-12-10 4:00 ` [PATCH v4 3/5] misc: eeprom_93xx46: Implement eeprom_93xx46 DT bindings Cory Tusar
` (2 subsequent siblings)
4 siblings, 1 reply; 14+ messages in thread
From: Cory Tusar @ 2015-12-10 4:00 UTC (permalink / raw)
To: robh+dt, pawel.moll, mark.rutland, ijc+devicetree, galak, gregkh
Cc: jic23, vz, broonie, afd, andrew, Chris.Healy, Keith.Vennel,
devicetree, linux-kernel, Cory Tusar
This commit documents bindings to be added to the eeprom_93xx46 driver
which will allow:
- Device word size and read-only attributes to be specified.
- A device-specific compatible string for use with Atmel AT93C46D
EEPROMs.
- Specifying a GPIO line to function as a 'select' or 'enable' signal
prior to accessing the EEPROM.
Signed-off-by: Cory Tusar <cory.tusar@pid1solutions.com>
Acked-by: Rob Herring <robh@kernel.org>
Tested-by: Chris Healy <chris.healy@zii.aero>
---
.../devicetree/bindings/misc/eeprom-93xx46.txt | 25 ++++++++++++++++++++++
1 file changed, 25 insertions(+)
diff --git a/Documentation/devicetree/bindings/misc/eeprom-93xx46.txt b/Documentation/devicetree/bindings/misc/eeprom-93xx46.txt
new file mode 100644
index 0000000..a8ebb46
--- /dev/null
+++ b/Documentation/devicetree/bindings/misc/eeprom-93xx46.txt
@@ -0,0 +1,25 @@
+EEPROMs (SPI) compatible with Microchip Technology 93xx46 family.
+
+Required properties:
+- compatible : shall be one of:
+ "atmel,at93c46d"
+ "eeprom-93xx46"
+- data-size : number of data bits per word (either 8 or 16)
+
+Optional properties:
+- read-only : parameter-less property which disables writes to the EEPROM
+- select-gpios : if present, specifies the GPIO that will be asserted prior to
+ each access to the EEPROM (e.g. for SPI bus multiplexing)
+
+Property rules described in Documentation/devicetree/bindings/spi/spi-bus.txt
+apply. In particular, "reg" and "spi-max-frequency" properties must be given.
+
+Example:
+ eeprom@0 {
+ compatible = "eeprom-93xx46";
+ reg = <0>;
+ spi-max-frequency = <1000000>;
+ spi-cs-high;
+ data-size = <8>;
+ select-gpios = <&gpio4 4 GPIO_ACTIVE_HIGH>;
+ };
--
2.4.10
^ permalink raw reply related [flat|nested] 14+ messages in thread
* [PATCH v4 3/5] misc: eeprom_93xx46: Implement eeprom_93xx46 DT bindings.
2015-12-10 4:00 [PATCH v4 0/5] Devicetree support for misc/eeprom/eeprom_93xx46 Cory Tusar
[not found] ` <1449720055-25965-1-git-send-email-cory.tusar-J6Z/VSE8EyIAspv4Qr0y0gC/G2K4zDHf@public.gmane.org>
2015-12-10 4:00 ` [PATCH v4 2/5] Documentation: devicetree: Add DT bindings to eeprom_93xx46 driver Cory Tusar
@ 2015-12-10 4:00 ` Cory Tusar
2015-12-22 0:12 ` Vladimir Zapolskiy
2015-12-10 4:00 ` [PATCH v4 4/5] misc: eeprom_93xx46: Add quirks to support Atmel AT93C46D device Cory Tusar
2015-12-10 4:00 ` [PATCH v4 5/5] misc: eeprom_93xx46: Add support for a GPIO 'select' line Cory Tusar
4 siblings, 1 reply; 14+ messages in thread
From: Cory Tusar @ 2015-12-10 4:00 UTC (permalink / raw)
To: robh+dt, pawel.moll, mark.rutland, ijc+devicetree, galak, gregkh
Cc: jic23, vz, broonie, afd, andrew, Chris.Healy, Keith.Vennel,
devicetree, linux-kernel, Cory Tusar
This commit implements bindings in the eeprom_93xx46 driver allowing
device word size and read-only attributes to be specified via
devicetree.
Signed-off-by: Cory Tusar <cory.tusar@pid1solutions.com>
Tested-by: Chris Healy <chris.healy@zii.aero>
---
drivers/misc/eeprom/eeprom_93xx46.c | 49 +++++++++++++++++++++++++++++++++++++
1 file changed, 49 insertions(+)
diff --git a/drivers/misc/eeprom/eeprom_93xx46.c b/drivers/misc/eeprom/eeprom_93xx46.c
index e1bf0a5..cc27e11 100644
--- a/drivers/misc/eeprom/eeprom_93xx46.c
+++ b/drivers/misc/eeprom/eeprom_93xx46.c
@@ -13,6 +13,8 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/sysfs.h>
@@ -294,12 +296,58 @@ static ssize_t eeprom_93xx46_store_erase(struct device *dev,
}
static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase);
+static const struct of_device_id eeprom_93xx46_of_table[] = {
+ { .compatible = "eeprom-93xx46", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, eeprom_93xx46_of_table);
+
+static int eeprom_93xx46_probe_dt(struct spi_device *spi)
+{
+ struct device_node *np = spi->dev.of_node;
+ struct eeprom_93xx46_platform_data *pd;
+ u32 tmp;
+ int ret;
+
+ pd = devm_kzalloc(&spi->dev, sizeof(*pd), GFP_KERNEL);
+ if (!pd)
+ return -ENOMEM;
+
+ ret = of_property_read_u32(np, "data-size", &tmp);
+ if (ret < 0) {
+ dev_err(&spi->dev, "data-size property not found\n");
+ return ret;
+ }
+
+ if (tmp == 8) {
+ pd->flags |= EE_ADDR8;
+ } else if (tmp == 16) {
+ pd->flags |= EE_ADDR16;
+ } else {
+ dev_err(&spi->dev, "invalid data-size (%d)\n", tmp);
+ return -EINVAL;
+ }
+
+ if (of_property_read_bool(np, "read-only"))
+ pd->flags |= EE_READONLY;
+
+ spi->dev.platform_data = pd;
+
+ return 0;
+}
+
static int eeprom_93xx46_probe(struct spi_device *spi)
{
struct eeprom_93xx46_platform_data *pd;
struct eeprom_93xx46_dev *edev;
int err;
+ if (spi->dev.of_node) {
+ err = eeprom_93xx46_probe_dt(spi);
+ if (err < 0)
+ return err;
+ }
+
pd = spi->dev.platform_data;
if (!pd) {
dev_err(&spi->dev, "missing platform data\n");
@@ -370,6 +418,7 @@ static int eeprom_93xx46_remove(struct spi_device *spi)
static struct spi_driver eeprom_93xx46_driver = {
.driver = {
.name = "93xx46",
+ .of_match_table = of_match_ptr(eeprom_93xx46_of_table),
},
.probe = eeprom_93xx46_probe,
.remove = eeprom_93xx46_remove,
--
2.4.10
^ permalink raw reply related [flat|nested] 14+ messages in thread
* Re: [PATCH v4 3/5] misc: eeprom_93xx46: Implement eeprom_93xx46 DT bindings.
2015-12-10 4:00 ` [PATCH v4 3/5] misc: eeprom_93xx46: Implement eeprom_93xx46 DT bindings Cory Tusar
@ 2015-12-22 0:12 ` Vladimir Zapolskiy
[not found] ` <5678955B.4070700-ChpfBGZJDbMAvxtiuMwx3w@public.gmane.org>
0 siblings, 1 reply; 14+ messages in thread
From: Vladimir Zapolskiy @ 2015-12-22 0:12 UTC (permalink / raw)
To: Cory Tusar, robh+dt, pawel.moll, mark.rutland, ijc+devicetree,
galak, gregkh
Cc: jic23, broonie, afd, andrew, Chris.Healy, Keith.Vennel,
devicetree, linux-kernel
Hi Cory,
On 10.12.2015 06:00, Cory Tusar wrote:
> This commit implements bindings in the eeprom_93xx46 driver allowing
> device word size and read-only attributes to be specified via
> devicetree.
>
> Signed-off-by: Cory Tusar <cory.tusar@pid1solutions.com>
> Tested-by: Chris Healy <chris.healy@zii.aero>
> ---
> drivers/misc/eeprom/eeprom_93xx46.c | 49 +++++++++++++++++++++++++++++++++++++
> 1 file changed, 49 insertions(+)
>
> diff --git a/drivers/misc/eeprom/eeprom_93xx46.c b/drivers/misc/eeprom/eeprom_93xx46.c
> index e1bf0a5..cc27e11 100644
> --- a/drivers/misc/eeprom/eeprom_93xx46.c
> +++ b/drivers/misc/eeprom/eeprom_93xx46.c
> @@ -13,6 +13,8 @@
> #include <linux/kernel.h>
> #include <linux/module.h>
> #include <linux/mutex.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> #include <linux/slab.h>
> #include <linux/spi/spi.h>
> #include <linux/sysfs.h>
> @@ -294,12 +296,58 @@ static ssize_t eeprom_93xx46_store_erase(struct device *dev,
> }
> static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase);
>
> +static const struct of_device_id eeprom_93xx46_of_table[] = {
> + { .compatible = "eeprom-93xx46", },
immediately do you want to add the second (and much, much more preferred IMO)
mentioned compatible value "atmel,at93c46d" to the list? Also see a note
below.
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, eeprom_93xx46_of_table);
> +
> +static int eeprom_93xx46_probe_dt(struct spi_device *spi)
> +{
> + struct device_node *np = spi->dev.of_node;
> + struct eeprom_93xx46_platform_data *pd;
> + u32 tmp;
> + int ret;
> +
> + pd = devm_kzalloc(&spi->dev, sizeof(*pd), GFP_KERNEL);
> + if (!pd)
> + return -ENOMEM;
> +
> + ret = of_property_read_u32(np, "data-size", &tmp);
> + if (ret < 0) {
> + dev_err(&spi->dev, "data-size property not found\n");
> + return ret;
> + }
> +
> + if (tmp == 8) {
> + pd->flags |= EE_ADDR8;
> + } else if (tmp == 16) {
> + pd->flags |= EE_ADDR16;
> + } else {
> + dev_err(&spi->dev, "invalid data-size (%d)\n", tmp);
> + return -EINVAL;
> + }
If you insist on mandatory "data-size" property, could you please check
arch/x86/platform/ce4100/falconfalls.dts , does it require updates?
In that DTS you may find "atmel,at93c46" compatible value, is that kind
of devices covered by this driver? If yes, does it make sense to
add "atmel,at93c46" to the list of compatible values replacing
"atmel,at93c46d" ?
> +
> + if (of_property_read_bool(np, "read-only"))
> + pd->flags |= EE_READONLY;
> +
> + spi->dev.platform_data = pd;
> +
> + return 0;
> +}
> +
> static int eeprom_93xx46_probe(struct spi_device *spi)
> {
> struct eeprom_93xx46_platform_data *pd;
> struct eeprom_93xx46_dev *edev;
> int err;
>
> + if (spi->dev.of_node) {
> + err = eeprom_93xx46_probe_dt(spi);
> + if (err < 0)
> + return err;
> + }
> +
> pd = spi->dev.platform_data;
> if (!pd) {
> dev_err(&spi->dev, "missing platform data\n");
> @@ -370,6 +418,7 @@ static int eeprom_93xx46_remove(struct spi_device *spi)
> static struct spi_driver eeprom_93xx46_driver = {
> .driver = {
> .name = "93xx46",
> + .of_match_table = of_match_ptr(eeprom_93xx46_of_table),
> },
> .probe = eeprom_93xx46_probe,
> .remove = eeprom_93xx46_remove,
>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
--
With best wishes,
Vladimir
^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH v4 4/5] misc: eeprom_93xx46: Add quirks to support Atmel AT93C46D device.
2015-12-10 4:00 [PATCH v4 0/5] Devicetree support for misc/eeprom/eeprom_93xx46 Cory Tusar
` (2 preceding siblings ...)
2015-12-10 4:00 ` [PATCH v4 3/5] misc: eeprom_93xx46: Implement eeprom_93xx46 DT bindings Cory Tusar
@ 2015-12-10 4:00 ` Cory Tusar
2015-12-22 0:19 ` Vladimir Zapolskiy
2015-12-10 4:00 ` [PATCH v4 5/5] misc: eeprom_93xx46: Add support for a GPIO 'select' line Cory Tusar
4 siblings, 1 reply; 14+ messages in thread
From: Cory Tusar @ 2015-12-10 4:00 UTC (permalink / raw)
To: robh+dt, pawel.moll, mark.rutland, ijc+devicetree, galak, gregkh
Cc: jic23, vz, broonie, afd, andrew, Chris.Healy, Keith.Vennel,
devicetree, linux-kernel, Cory Tusar
Atmel devices in this family have some quirks not found in other similar
chips - they do not support a sequential read of the entire EEPROM
contents, and the control word sent at the start of each operation
varies in bit length.
This commit adds quirk support to the driver and modifies the read
implementation to support non-sequential reads for consistency with
other misc/eeprom drivers.
Tested on a custom Freescale VF610-based platform, with an AT93C46D
device attached via dspi2. The spi-gpio driver was used to allow the
necessary non-byte-sized transfers.
Signed-off-by: Cory Tusar <cory.tusar@pid1solutions.com>
Tested-by: Chris Healy <chris.healy@zii.aero>
---
drivers/misc/eeprom/eeprom_93xx46.c | 126 ++++++++++++++++++++++++++----------
include/linux/eeprom_93xx46.h | 6 ++
2 files changed, 97 insertions(+), 35 deletions(-)
diff --git a/drivers/misc/eeprom/eeprom_93xx46.c b/drivers/misc/eeprom/eeprom_93xx46.c
index cc27e11..d50bc17 100644
--- a/drivers/misc/eeprom/eeprom_93xx46.c
+++ b/drivers/misc/eeprom/eeprom_93xx46.c
@@ -27,6 +27,15 @@
#define ADDR_ERAL 0x20
#define ADDR_EWEN 0x30
+struct eeprom_93xx46_devtype_data {
+ unsigned int quirks;
+};
+
+static const struct eeprom_93xx46_devtype_data atmel_at93c46d_data = {
+ .quirks = EEPROM_93XX46_QUIRK_SINGLE_WORD_READ |
+ EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH,
+};
+
struct eeprom_93xx46_dev {
struct spi_device *spi;
struct eeprom_93xx46_platform_data *pdata;
@@ -35,6 +44,16 @@ struct eeprom_93xx46_dev {
int addrlen;
};
+static inline bool has_quirk_single_word_read(struct eeprom_93xx46_dev *edev)
+{
+ return edev->pdata->quirks & EEPROM_93XX46_QUIRK_SINGLE_WORD_READ;
+}
+
+static inline bool has_quirk_instruction_length(struct eeprom_93xx46_dev *edev)
+{
+ return edev->pdata->quirks & EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH;
+}
+
static ssize_t
eeprom_93xx46_bin_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *bin_attr,
@@ -42,58 +61,73 @@ eeprom_93xx46_bin_read(struct file *filp, struct kobject *kobj,
{
struct eeprom_93xx46_dev *edev;
struct device *dev;
- struct spi_message m;
- struct spi_transfer t[2];
- int bits, ret;
- u16 cmd_addr;
+ ssize_t ret = 0;
dev = container_of(kobj, struct device, kobj);
edev = dev_get_drvdata(dev);
- cmd_addr = OP_READ << edev->addrlen;
+ mutex_lock(&edev->lock);
- if (edev->addrlen == 7) {
- cmd_addr |= off & 0x7f;
- bits = 10;
- } else {
- cmd_addr |= (off >> 1) & 0x3f;
- bits = 9;
- }
+ if (edev->pdata->prepare)
+ edev->pdata->prepare(edev);
- dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n",
- cmd_addr, edev->spi->max_speed_hz);
+ while (count) {
+ struct spi_message m;
+ struct spi_transfer t[2] = { { 0 } };
+ u16 cmd_addr = OP_READ << edev->addrlen;
+ size_t nbytes = count;
+ int bits;
+ int err;
+
+ if (edev->addrlen == 7) {
+ cmd_addr |= off & 0x7f;
+ bits = 10;
+ if (has_quirk_single_word_read(edev))
+ nbytes = 1;
+ } else {
+ cmd_addr |= (off >> 1) & 0x3f;
+ bits = 9;
+ if (has_quirk_single_word_read(edev))
+ nbytes = 2;
+ }
- spi_message_init(&m);
- memset(t, 0, sizeof(t));
+ dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n",
+ cmd_addr, edev->spi->max_speed_hz);
- t[0].tx_buf = (char *)&cmd_addr;
- t[0].len = 2;
- t[0].bits_per_word = bits;
- spi_message_add_tail(&t[0], &m);
+ spi_message_init(&m);
- t[1].rx_buf = buf;
- t[1].len = count;
- t[1].bits_per_word = 8;
- spi_message_add_tail(&t[1], &m);
+ t[0].tx_buf = (char *)&cmd_addr;
+ t[0].len = 2;
+ t[0].bits_per_word = bits;
+ spi_message_add_tail(&t[0], &m);
- mutex_lock(&edev->lock);
+ t[1].rx_buf = buf;
+ t[1].len = count;
+ t[1].bits_per_word = 8;
+ spi_message_add_tail(&t[1], &m);
- if (edev->pdata->prepare)
- edev->pdata->prepare(edev);
+ err = spi_sync(edev->spi, &m);
+ /* have to wait at least Tcsl ns */
+ ndelay(250);
- ret = spi_sync(edev->spi, &m);
- /* have to wait at least Tcsl ns */
- ndelay(250);
- if (ret) {
- dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n",
- count, (int)off, ret);
+ if (err) {
+ dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n",
+ nbytes, (int)off, err);
+ ret = err;
+ break;
+ }
+
+ buf += nbytes;
+ off += nbytes;
+ count -= nbytes;
+ ret += nbytes;
}
if (edev->pdata->finish)
edev->pdata->finish(edev);
mutex_unlock(&edev->lock);
- return ret ? : count;
+ return ret;
}
static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on)
@@ -112,7 +146,13 @@ static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on)
bits = 9;
}
- dev_dbg(&edev->spi->dev, "ew cmd 0x%04x\n", cmd_addr);
+ if (has_quirk_instruction_length(edev)) {
+ cmd_addr <<= 2;
+ bits += 2;
+ }
+
+ dev_dbg(&edev->spi->dev, "ew%s cmd 0x%04x, %d bits\n",
+ is_on ? "en" : "ds", cmd_addr, bits);
spi_message_init(&m);
memset(&t, 0, sizeof(t));
@@ -247,6 +287,13 @@ static int eeprom_93xx46_eral(struct eeprom_93xx46_dev *edev)
bits = 9;
}
+ if (has_quirk_instruction_length(edev)) {
+ cmd_addr <<= 2;
+ bits += 2;
+ }
+
+ dev_dbg(&edev->spi->dev, "eral cmd 0x%04x, %d bits\n", cmd_addr, bits);
+
spi_message_init(&m);
memset(&t, 0, sizeof(t));
@@ -298,12 +345,15 @@ static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase);
static const struct of_device_id eeprom_93xx46_of_table[] = {
{ .compatible = "eeprom-93xx46", },
+ { .compatible = "atmel,at93c46d", .data = &atmel_at93c46d_data, },
{}
};
MODULE_DEVICE_TABLE(of, eeprom_93xx46_of_table);
static int eeprom_93xx46_probe_dt(struct spi_device *spi)
{
+ const struct of_device_id *of_id =
+ of_match_device(eeprom_93xx46_of_table, &spi->dev);
struct device_node *np = spi->dev.of_node;
struct eeprom_93xx46_platform_data *pd;
u32 tmp;
@@ -331,6 +381,12 @@ static int eeprom_93xx46_probe_dt(struct spi_device *spi)
if (of_property_read_bool(np, "read-only"))
pd->flags |= EE_READONLY;
+ if (of_id->data) {
+ const struct eeprom_93xx46_devtype_data *data = of_id->data;
+
+ pd->quirks = data->quirks;
+ }
+
spi->dev.platform_data = pd;
return 0;
diff --git a/include/linux/eeprom_93xx46.h b/include/linux/eeprom_93xx46.h
index 0679181..92fa4c3 100644
--- a/include/linux/eeprom_93xx46.h
+++ b/include/linux/eeprom_93xx46.h
@@ -9,6 +9,12 @@ struct eeprom_93xx46_platform_data {
#define EE_ADDR16 0x02 /* 16 bit addr. cfg */
#define EE_READONLY 0x08 /* forbid writing */
+ unsigned int quirks;
+/* Single word read transfers only; no sequential read. */
+#define EEPROM_93XX46_QUIRK_SINGLE_WORD_READ (1 << 0)
+/* Instructions such as EWEN are (addrlen + 2) in length. */
+#define EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH (1 << 1)
+
/*
* optional hooks to control additional logic
* before and after spi transfer.
--
2.4.10
^ permalink raw reply related [flat|nested] 14+ messages in thread
* Re: [PATCH v4 4/5] misc: eeprom_93xx46: Add quirks to support Atmel AT93C46D device.
2015-12-10 4:00 ` [PATCH v4 4/5] misc: eeprom_93xx46: Add quirks to support Atmel AT93C46D device Cory Tusar
@ 2015-12-22 0:19 ` Vladimir Zapolskiy
2016-01-06 3:20 ` Cory Tusar
0 siblings, 1 reply; 14+ messages in thread
From: Vladimir Zapolskiy @ 2015-12-22 0:19 UTC (permalink / raw)
To: Cory Tusar, robh+dt, pawel.moll, mark.rutland, ijc+devicetree,
galak, gregkh
Cc: jic23, broonie, afd, andrew, Chris.Healy, Keith.Vennel,
devicetree, linux-kernel
With best wishes,
Vladimir
On 10.12.2015 06:00, Cory Tusar wrote:
> Atmel devices in this family have some quirks not found in other similar
> chips - they do not support a sequential read of the entire EEPROM
> contents, and the control word sent at the start of each operation
> varies in bit length.
>
> This commit adds quirk support to the driver and modifies the read
> implementation to support non-sequential reads for consistency with
> other misc/eeprom drivers.
>
> Tested on a custom Freescale VF610-based platform, with an AT93C46D
> device attached via dspi2. The spi-gpio driver was used to allow the
> necessary non-byte-sized transfers.
>
> Signed-off-by: Cory Tusar <cory.tusar@pid1solutions.com>
> Tested-by: Chris Healy <chris.healy@zii.aero>
> ---
> drivers/misc/eeprom/eeprom_93xx46.c | 126 ++++++++++++++++++++++++++----------
> include/linux/eeprom_93xx46.h | 6 ++
> 2 files changed, 97 insertions(+), 35 deletions(-)
>
> diff --git a/drivers/misc/eeprom/eeprom_93xx46.c b/drivers/misc/eeprom/eeprom_93xx46.c
> index cc27e11..d50bc17 100644
> --- a/drivers/misc/eeprom/eeprom_93xx46.c
> +++ b/drivers/misc/eeprom/eeprom_93xx46.c
> @@ -27,6 +27,15 @@
> #define ADDR_ERAL 0x20
> #define ADDR_EWEN 0x30
>
> +struct eeprom_93xx46_devtype_data {
> + unsigned int quirks;
> +};
> +
> +static const struct eeprom_93xx46_devtype_data atmel_at93c46d_data = {
> + .quirks = EEPROM_93XX46_QUIRK_SINGLE_WORD_READ |
> + EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH,
> +};
> +
> struct eeprom_93xx46_dev {
> struct spi_device *spi;
> struct eeprom_93xx46_platform_data *pdata;
> @@ -35,6 +44,16 @@ struct eeprom_93xx46_dev {
> int addrlen;
> };
>
> +static inline bool has_quirk_single_word_read(struct eeprom_93xx46_dev *edev)
> +{
> + return edev->pdata->quirks & EEPROM_93XX46_QUIRK_SINGLE_WORD_READ;
> +}
> +
> +static inline bool has_quirk_instruction_length(struct eeprom_93xx46_dev *edev)
> +{
> + return edev->pdata->quirks & EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH;
> +}
> +
> static ssize_t
> eeprom_93xx46_bin_read(struct file *filp, struct kobject *kobj,
> struct bin_attribute *bin_attr,
> @@ -42,58 +61,73 @@ eeprom_93xx46_bin_read(struct file *filp, struct kobject *kobj,
> {
> struct eeprom_93xx46_dev *edev;
> struct device *dev;
> - struct spi_message m;
> - struct spi_transfer t[2];
> - int bits, ret;
> - u16 cmd_addr;
> + ssize_t ret = 0;
>
> dev = container_of(kobj, struct device, kobj);
> edev = dev_get_drvdata(dev);
>
> - cmd_addr = OP_READ << edev->addrlen;
> + mutex_lock(&edev->lock);
>
> - if (edev->addrlen == 7) {
> - cmd_addr |= off & 0x7f;
> - bits = 10;
> - } else {
> - cmd_addr |= (off >> 1) & 0x3f;
> - bits = 9;
> - }
> + if (edev->pdata->prepare)
> + edev->pdata->prepare(edev);
>
> - dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n",
> - cmd_addr, edev->spi->max_speed_hz);
> + while (count) {
> + struct spi_message m;
> + struct spi_transfer t[2] = { { 0 } };
> + u16 cmd_addr = OP_READ << edev->addrlen;
> + size_t nbytes = count;
> + int bits;
> + int err;
> +
> + if (edev->addrlen == 7) {
> + cmd_addr |= off & 0x7f;
> + bits = 10;
> + if (has_quirk_single_word_read(edev))
> + nbytes = 1;
> + } else {
> + cmd_addr |= (off >> 1) & 0x3f;
> + bits = 9;
> + if (has_quirk_single_word_read(edev))
> + nbytes = 2;
> + }
>
> - spi_message_init(&m);
> - memset(t, 0, sizeof(t));
> + dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n",
> + cmd_addr, edev->spi->max_speed_hz);
>
> - t[0].tx_buf = (char *)&cmd_addr;
> - t[0].len = 2;
> - t[0].bits_per_word = bits;
> - spi_message_add_tail(&t[0], &m);
> + spi_message_init(&m);
>
> - t[1].rx_buf = buf;
> - t[1].len = count;
> - t[1].bits_per_word = 8;
> - spi_message_add_tail(&t[1], &m);
> + t[0].tx_buf = (char *)&cmd_addr;
> + t[0].len = 2;
> + t[0].bits_per_word = bits;
> + spi_message_add_tail(&t[0], &m);
>
> - mutex_lock(&edev->lock);
> + t[1].rx_buf = buf;
> + t[1].len = count;
> + t[1].bits_per_word = 8;
> + spi_message_add_tail(&t[1], &m);
>
> - if (edev->pdata->prepare)
> - edev->pdata->prepare(edev);
> + err = spi_sync(edev->spi, &m);
> + /* have to wait at least Tcsl ns */
> + ndelay(250);
>
> - ret = spi_sync(edev->spi, &m);
> - /* have to wait at least Tcsl ns */
> - ndelay(250);
> - if (ret) {
> - dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n",
> - count, (int)off, ret);
> + if (err) {
> + dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n",
> + nbytes, (int)off, err);
> + ret = err;
> + break;
> + }
> +
> + buf += nbytes;
> + off += nbytes;
> + count -= nbytes;
> + ret += nbytes;
> }
>
> if (edev->pdata->finish)
> edev->pdata->finish(edev);
>
> mutex_unlock(&edev->lock);
> - return ret ? : count;
> + return ret;
> }
>
> static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on)
> @@ -112,7 +146,13 @@ static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on)
> bits = 9;
> }
>
> - dev_dbg(&edev->spi->dev, "ew cmd 0x%04x\n", cmd_addr);
> + if (has_quirk_instruction_length(edev)) {
> + cmd_addr <<= 2;
> + bits += 2;
> + }
> +
> + dev_dbg(&edev->spi->dev, "ew%s cmd 0x%04x, %d bits\n",
> + is_on ? "en" : "ds", cmd_addr, bits);
>
> spi_message_init(&m);
> memset(&t, 0, sizeof(t));
> @@ -247,6 +287,13 @@ static int eeprom_93xx46_eral(struct eeprom_93xx46_dev *edev)
> bits = 9;
> }
>
> + if (has_quirk_instruction_length(edev)) {
> + cmd_addr <<= 2;
> + bits += 2;
> + }
> +
> + dev_dbg(&edev->spi->dev, "eral cmd 0x%04x, %d bits\n", cmd_addr, bits);
> +
> spi_message_init(&m);
> memset(&t, 0, sizeof(t));
>
> @@ -298,12 +345,15 @@ static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase);
>
> static const struct of_device_id eeprom_93xx46_of_table[] = {
> { .compatible = "eeprom-93xx46", },
> + { .compatible = "atmel,at93c46d", .data = &atmel_at93c46d_data, },
Ok, got the second "atmel,at93c46d" here.
> {}
> };
> MODULE_DEVICE_TABLE(of, eeprom_93xx46_of_table);
>
> static int eeprom_93xx46_probe_dt(struct spi_device *spi)
> {
> + const struct of_device_id *of_id =
> + of_match_device(eeprom_93xx46_of_table, &spi->dev);
> struct device_node *np = spi->dev.of_node;
> struct eeprom_93xx46_platform_data *pd;
> u32 tmp;
> @@ -331,6 +381,12 @@ static int eeprom_93xx46_probe_dt(struct spi_device *spi)
> if (of_property_read_bool(np, "read-only"))
> pd->flags |= EE_READONLY;
>
> + if (of_id->data) {
> + const struct eeprom_93xx46_devtype_data *data = of_id->data;
> +
> + pd->quirks = data->quirks;
> + }
> +
> spi->dev.platform_data = pd;
>
> return 0;
> diff --git a/include/linux/eeprom_93xx46.h b/include/linux/eeprom_93xx46.h
> index 0679181..92fa4c3 100644
> --- a/include/linux/eeprom_93xx46.h
> +++ b/include/linux/eeprom_93xx46.h
> @@ -9,6 +9,12 @@ struct eeprom_93xx46_platform_data {
> #define EE_ADDR16 0x02 /* 16 bit addr. cfg */
> #define EE_READONLY 0x08 /* forbid writing */
>
> + unsigned int quirks;
> +/* Single word read transfers only; no sequential read. */
> +#define EEPROM_93XX46_QUIRK_SINGLE_WORD_READ (1 << 0)
> +/* Instructions such as EWEN are (addrlen + 2) in length. */
> +#define EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH (1 << 1)
> +
> /*
> * optional hooks to control additional logic
> * before and after spi transfer.
>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
--
With best wishes,
Vladimir
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH v4 4/5] misc: eeprom_93xx46: Add quirks to support Atmel AT93C46D device.
2015-12-22 0:19 ` Vladimir Zapolskiy
@ 2016-01-06 3:20 ` Cory Tusar
0 siblings, 0 replies; 14+ messages in thread
From: Cory Tusar @ 2016-01-06 3:20 UTC (permalink / raw)
To: Vladimir Zapolskiy, robh+dt, pawel.moll, mark.rutland,
ijc+devicetree, galak, gregkh
Cc: jic23, broonie, afd, andrew, Chris.Healy, Keith.Vennel,
devicetree, linux-kernel
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
On 12/21/2015 07:19 PM, Vladimir Zapolskiy wrote:
>
>
> With best wishes,
> Vladimir
>
> On 10.12.2015 06:00, Cory Tusar wrote:
>> Atmel devices in this family have some quirks not found in other similar
>> chips - they do not support a sequential read of the entire EEPROM
>> contents, and the control word sent at the start of each operation
>> varies in bit length.
>>
>> This commit adds quirk support to the driver and modifies the read
>> implementation to support non-sequential reads for consistency with
>> other misc/eeprom drivers.
>>
>> Tested on a custom Freescale VF610-based platform, with an AT93C46D
>> device attached via dspi2. The spi-gpio driver was used to allow the
>> necessary non-byte-sized transfers.
>>
>> Signed-off-by: Cory Tusar <cory.tusar@pid1solutions.com>
>> Tested-by: Chris Healy <chris.healy@zii.aero>
>> ---
>> drivers/misc/eeprom/eeprom_93xx46.c | 126 ++++++++++++++++++++++++++----------
>> include/linux/eeprom_93xx46.h | 6 ++
>> 2 files changed, 97 insertions(+), 35 deletions(-)
>>
>> diff --git a/drivers/misc/eeprom/eeprom_93xx46.c b/drivers/misc/eeprom/eeprom_93xx46.c
>> index cc27e11..d50bc17 100644
>> --- a/drivers/misc/eeprom/eeprom_93xx46.c
>> +++ b/drivers/misc/eeprom/eeprom_93xx46.c
>> @@ -27,6 +27,15 @@
>> #define ADDR_ERAL 0x20
>> #define ADDR_EWEN 0x30
>>
>> +struct eeprom_93xx46_devtype_data {
>> + unsigned int quirks;
>> +};
>> +
>> +static const struct eeprom_93xx46_devtype_data atmel_at93c46d_data = {
>> + .quirks = EEPROM_93XX46_QUIRK_SINGLE_WORD_READ |
>> + EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH,
>> +};
>> +
>> struct eeprom_93xx46_dev {
>> struct spi_device *spi;
>> struct eeprom_93xx46_platform_data *pdata;
>> @@ -35,6 +44,16 @@ struct eeprom_93xx46_dev {
>> int addrlen;
>> };
>>
>> +static inline bool has_quirk_single_word_read(struct eeprom_93xx46_dev *edev)
>> +{
>> + return edev->pdata->quirks & EEPROM_93XX46_QUIRK_SINGLE_WORD_READ;
>> +}
>> +
>> +static inline bool has_quirk_instruction_length(struct eeprom_93xx46_dev *edev)
>> +{
>> + return edev->pdata->quirks & EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH;
>> +}
>> +
>> static ssize_t
>> eeprom_93xx46_bin_read(struct file *filp, struct kobject *kobj,
>> struct bin_attribute *bin_attr,
>> @@ -42,58 +61,73 @@ eeprom_93xx46_bin_read(struct file *filp, struct kobject *kobj,
>> {
>> struct eeprom_93xx46_dev *edev;
>> struct device *dev;
>> - struct spi_message m;
>> - struct spi_transfer t[2];
>> - int bits, ret;
>> - u16 cmd_addr;
>> + ssize_t ret = 0;
>>
>> dev = container_of(kobj, struct device, kobj);
>> edev = dev_get_drvdata(dev);
>>
>> - cmd_addr = OP_READ << edev->addrlen;
>> + mutex_lock(&edev->lock);
>>
>> - if (edev->addrlen == 7) {
>> - cmd_addr |= off & 0x7f;
>> - bits = 10;
>> - } else {
>> - cmd_addr |= (off >> 1) & 0x3f;
>> - bits = 9;
>> - }
>> + if (edev->pdata->prepare)
>> + edev->pdata->prepare(edev);
>>
>> - dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n",
>> - cmd_addr, edev->spi->max_speed_hz);
>> + while (count) {
>> + struct spi_message m;
>> + struct spi_transfer t[2] = { { 0 } };
>> + u16 cmd_addr = OP_READ << edev->addrlen;
>> + size_t nbytes = count;
>> + int bits;
>> + int err;
>> +
>> + if (edev->addrlen == 7) {
>> + cmd_addr |= off & 0x7f;
>> + bits = 10;
>> + if (has_quirk_single_word_read(edev))
>> + nbytes = 1;
>> + } else {
>> + cmd_addr |= (off >> 1) & 0x3f;
>> + bits = 9;
>> + if (has_quirk_single_word_read(edev))
>> + nbytes = 2;
>> + }
>>
>> - spi_message_init(&m);
>> - memset(t, 0, sizeof(t));
>> + dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n",
>> + cmd_addr, edev->spi->max_speed_hz);
>>
>> - t[0].tx_buf = (char *)&cmd_addr;
>> - t[0].len = 2;
>> - t[0].bits_per_word = bits;
>> - spi_message_add_tail(&t[0], &m);
>> + spi_message_init(&m);
>>
>> - t[1].rx_buf = buf;
>> - t[1].len = count;
>> - t[1].bits_per_word = 8;
>> - spi_message_add_tail(&t[1], &m);
>> + t[0].tx_buf = (char *)&cmd_addr;
>> + t[0].len = 2;
>> + t[0].bits_per_word = bits;
>> + spi_message_add_tail(&t[0], &m);
>>
>> - mutex_lock(&edev->lock);
>> + t[1].rx_buf = buf;
>> + t[1].len = count;
>> + t[1].bits_per_word = 8;
>> + spi_message_add_tail(&t[1], &m);
>>
>> - if (edev->pdata->prepare)
>> - edev->pdata->prepare(edev);
>> + err = spi_sync(edev->spi, &m);
>> + /* have to wait at least Tcsl ns */
>> + ndelay(250);
>>
>> - ret = spi_sync(edev->spi, &m);
>> - /* have to wait at least Tcsl ns */
>> - ndelay(250);
>> - if (ret) {
>> - dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n",
>> - count, (int)off, ret);
>> + if (err) {
>> + dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n",
>> + nbytes, (int)off, err);
>> + ret = err;
>> + break;
>> + }
>> +
>> + buf += nbytes;
>> + off += nbytes;
>> + count -= nbytes;
>> + ret += nbytes;
>> }
>>
>> if (edev->pdata->finish)
>> edev->pdata->finish(edev);
>>
>> mutex_unlock(&edev->lock);
>> - return ret ? : count;
>> + return ret;
>> }
>>
>> static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on)
>> @@ -112,7 +146,13 @@ static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on)
>> bits = 9;
>> }
>>
>> - dev_dbg(&edev->spi->dev, "ew cmd 0x%04x\n", cmd_addr);
>> + if (has_quirk_instruction_length(edev)) {
>> + cmd_addr <<= 2;
>> + bits += 2;
>> + }
>> +
>> + dev_dbg(&edev->spi->dev, "ew%s cmd 0x%04x, %d bits\n",
>> + is_on ? "en" : "ds", cmd_addr, bits);
>>
>> spi_message_init(&m);
>> memset(&t, 0, sizeof(t));
>> @@ -247,6 +287,13 @@ static int eeprom_93xx46_eral(struct eeprom_93xx46_dev *edev)
>> bits = 9;
>> }
>>
>> + if (has_quirk_instruction_length(edev)) {
>> + cmd_addr <<= 2;
>> + bits += 2;
>> + }
>> +
>> + dev_dbg(&edev->spi->dev, "eral cmd 0x%04x, %d bits\n", cmd_addr, bits);
>> +
>> spi_message_init(&m);
>> memset(&t, 0, sizeof(t));
>>
>> @@ -298,12 +345,15 @@ static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase);
>>
>> static const struct of_device_id eeprom_93xx46_of_table[] = {
>> { .compatible = "eeprom-93xx46", },
>> + { .compatible = "atmel,at93c46d", .data = &atmel_at93c46d_data, },
>
> Ok, got the second "atmel,at93c46d" here.
Yeah.
>
>> {}
>> };
>> MODULE_DEVICE_TABLE(of, eeprom_93xx46_of_table);
>>
>> static int eeprom_93xx46_probe_dt(struct spi_device *spi)
>> {
>> + const struct of_device_id *of_id =
>> + of_match_device(eeprom_93xx46_of_table, &spi->dev);
>> struct device_node *np = spi->dev.of_node;
>> struct eeprom_93xx46_platform_data *pd;
>> u32 tmp;
>> @@ -331,6 +381,12 @@ static int eeprom_93xx46_probe_dt(struct spi_device *spi)
>> if (of_property_read_bool(np, "read-only"))
>> pd->flags |= EE_READONLY;
>>
>> + if (of_id->data) {
>> + const struct eeprom_93xx46_devtype_data *data = of_id->data;
>> +
>> + pd->quirks = data->quirks;
>> + }
>> +
>> spi->dev.platform_data = pd;
>>
>> return 0;
>> diff --git a/include/linux/eeprom_93xx46.h b/include/linux/eeprom_93xx46.h
>> index 0679181..92fa4c3 100644
>> --- a/include/linux/eeprom_93xx46.h
>> +++ b/include/linux/eeprom_93xx46.h
>> @@ -9,6 +9,12 @@ struct eeprom_93xx46_platform_data {
>> #define EE_ADDR16 0x02 /* 16 bit addr. cfg */
>> #define EE_READONLY 0x08 /* forbid writing */
>>
>> + unsigned int quirks;
>> +/* Single word read transfers only; no sequential read. */
>> +#define EEPROM_93XX46_QUIRK_SINGLE_WORD_READ (1 << 0)
>> +/* Instructions such as EWEN are (addrlen + 2) in length. */
>> +#define EEPROM_93XX46_QUIRK_INSTRUCTION_LENGTH (1 << 1)
>> +
>> /*
>> * optional hooks to control additional logic
>> * before and after spi transfer.
>>
>
> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Thanks again for all the reviews.
Best regards,
- -Cory
- --
Cory Tusar
Principal
PID 1 Solutions, Inc.
"There are two ways of constructing a software design. One way is to
make it so simple that there are obviously no deficiencies, and the
other way is to make it so complicated that there are no obvious
deficiencies." --Sir Charles Anthony Richard Hoare
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* [PATCH v4 5/5] misc: eeprom_93xx46: Add support for a GPIO 'select' line.
2015-12-10 4:00 [PATCH v4 0/5] Devicetree support for misc/eeprom/eeprom_93xx46 Cory Tusar
` (3 preceding siblings ...)
2015-12-10 4:00 ` [PATCH v4 4/5] misc: eeprom_93xx46: Add quirks to support Atmel AT93C46D device Cory Tusar
@ 2015-12-10 4:00 ` Cory Tusar
[not found] ` <1449720055-25965-6-git-send-email-cory.tusar-J6Z/VSE8EyIAspv4Qr0y0gC/G2K4zDHf@public.gmane.org>
4 siblings, 1 reply; 14+ messages in thread
From: Cory Tusar @ 2015-12-10 4:00 UTC (permalink / raw)
To: robh+dt, pawel.moll, mark.rutland, ijc+devicetree, galak, gregkh
Cc: jic23, vz, broonie, afd, andrew, Chris.Healy, Keith.Vennel,
devicetree, linux-kernel, Cory Tusar
This commit adds support to the eeprom_93x46 driver allowing a GPIO line
to function as a 'select' or 'enable' signal prior to accessing the
EEPROM.
Signed-off-by: Cory Tusar <cory.tusar@pid1solutions.com>
Tested-by: Chris Healy <chris.healy@zii.aero>
---
drivers/misc/eeprom/eeprom_93xx46.c | 35 +++++++++++++++++++++++++++++++++++
include/linux/eeprom_93xx46.h | 3 +++
2 files changed, 38 insertions(+)
diff --git a/drivers/misc/eeprom/eeprom_93xx46.c b/drivers/misc/eeprom/eeprom_93xx46.c
index d50bc17..d28fac2 100644
--- a/drivers/misc/eeprom/eeprom_93xx46.c
+++ b/drivers/misc/eeprom/eeprom_93xx46.c
@@ -10,11 +10,13 @@
#include <linux/delay.h>
#include <linux/device.h>
+#include <linux/gpio/consumer.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/of_device.h>
+#include <linux/of_gpio.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/sysfs.h>
@@ -343,6 +345,20 @@ static ssize_t eeprom_93xx46_store_erase(struct device *dev,
}
static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase);
+static void select_assert(void *context)
+{
+ struct eeprom_93xx46_dev *edev = context;
+
+ gpiod_set_value_cansleep(edev->pdata->select, 1);
+}
+
+static void select_deassert(void *context)
+{
+ struct eeprom_93xx46_dev *edev = context;
+
+ gpiod_set_value_cansleep(edev->pdata->select, 0);
+}
+
static const struct of_device_id eeprom_93xx46_of_table[] = {
{ .compatible = "eeprom-93xx46", },
{ .compatible = "atmel,at93c46d", .data = &atmel_at93c46d_data, },
@@ -357,6 +373,8 @@ static int eeprom_93xx46_probe_dt(struct spi_device *spi)
struct device_node *np = spi->dev.of_node;
struct eeprom_93xx46_platform_data *pd;
u32 tmp;
+ int gpio;
+ enum of_gpio_flags of_flags;
int ret;
pd = devm_kzalloc(&spi->dev, sizeof(*pd), GFP_KERNEL);
@@ -381,6 +399,23 @@ static int eeprom_93xx46_probe_dt(struct spi_device *spi)
if (of_property_read_bool(np, "read-only"))
pd->flags |= EE_READONLY;
+ gpio = of_get_named_gpio_flags(np, "select-gpios", 0, &of_flags);
+ if (gpio_is_valid(gpio)) {
+ unsigned long flags =
+ of_flags == OF_GPIO_ACTIVE_LOW ? GPIOF_ACTIVE_LOW : 0;
+
+ ret = devm_gpio_request_one(&spi->dev, gpio, flags,
+ "eeprom_93xx46_select");
+ if (ret)
+ return ret;
+
+ pd->select = gpio_to_desc(gpio);
+ pd->prepare = select_assert;
+ pd->finish = select_deassert;
+
+ gpiod_direction_output(pd->select, 0);
+ }
+
if (of_id->data) {
const struct eeprom_93xx46_devtype_data *data = of_id->data;
diff --git a/include/linux/eeprom_93xx46.h b/include/linux/eeprom_93xx46.h
index 92fa4c3..03f3435 100644
--- a/include/linux/eeprom_93xx46.h
+++ b/include/linux/eeprom_93xx46.h
@@ -3,6 +3,8 @@
* platform description for 93xx46 EEPROMs.
*/
+#include <linux/of_gpio.h>
+
struct eeprom_93xx46_platform_data {
unsigned char flags;
#define EE_ADDR8 0x01 /* 8 bit addr. cfg */
@@ -21,4 +23,5 @@ struct eeprom_93xx46_platform_data {
*/
void (*prepare)(void *);
void (*finish)(void *);
+ struct gpio_desc *select;
};
--
2.4.10
^ permalink raw reply related [flat|nested] 14+ messages in thread