2018-08-21 14:33:25

by Ricardo Ribalda Delgado

[permalink] [raw]
Subject: [PATCH 0/8] gpio-addr-flash: Support for device-tree and cleanup

This patch series does the following:

1) Fix bug regarding ioremap size
2) Cleanup code to use new APIs
3) Simplify numerical operations
4) Add support for device-tree devices

Thanks!

Ricardo Ribalda Delgado (8):
mtd: maps: gpio-addr-flash: Replace custom printk
mtd: maps: gpio-addr-flash: Fix ioremapped size
mtd: maps: gpio-addr-flash: Use devm_* functions
mtd: maps: gpio-addr-flash: Use order insted of size
mtd: maps: gpio-addr-flash: Replace array with an integer
mtd: maps: gpio-addr-flash: Split allocation in two
mtd: maps: gpio-addr-flash: Add support for device-tree devices
dt-binding: mtd: Document gpio-addr-flash

.../bindings/mtd/gpio-addr-flash.txt | 46 +++
drivers/mtd/maps/gpio-addr-flash.c | 277 ++++++++++++------
2 files changed, 237 insertions(+), 86 deletions(-)
create mode 100644 Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt

--
2.18.0



2018-08-21 14:33:25

by Ricardo Ribalda Delgado

[permalink] [raw]
Subject: [PATCH 2/8] mtd: maps: gpio-addr-flash: Fix ioremapped size

We should only iomap the area of the chip that is memory mapped.
Otherwise we could be mapping devices beyond the memory space or that
belong to other devices.

Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
---
drivers/mtd/maps/gpio-addr-flash.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/maps/gpio-addr-flash.c b/drivers/mtd/maps/gpio-addr-flash.c
index 17be47f72973..6de16e81994c 100644
--- a/drivers/mtd/maps/gpio-addr-flash.c
+++ b/drivers/mtd/maps/gpio-addr-flash.c
@@ -234,7 +234,7 @@ static int gpio_flash_probe(struct platform_device *pdev)
state->map.copy_to = gf_copy_to;
state->map.bankwidth = pdata->width;
state->map.size = state->win_size * (1 << state->gpio_count);
- state->map.virt = ioremap_nocache(memory->start, state->map.size);
+ state->map.virt = ioremap_nocache(memory->start, state->win_size);
if (!state->map.virt)
return -ENOMEM;

--
2.18.0


2018-08-21 14:33:25

by Ricardo Ribalda Delgado

[permalink] [raw]
Subject: [PATCH 3/8] mtd: maps: gpio-addr-flash: Use devm_* functions

By using devm functions we can make the code cleaner.

Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
---
drivers/mtd/maps/gpio-addr-flash.c | 28 ++++++++++------------------
1 file changed, 10 insertions(+), 18 deletions(-)

diff --git a/drivers/mtd/maps/gpio-addr-flash.c b/drivers/mtd/maps/gpio-addr-flash.c
index 6de16e81994c..54a0d7d2365a 100644
--- a/drivers/mtd/maps/gpio-addr-flash.c
+++ b/drivers/mtd/maps/gpio-addr-flash.c
@@ -213,7 +213,7 @@ static int gpio_flash_probe(struct platform_device *pdev)
return -EINVAL;

arr_size = sizeof(int) * gpios->end;
- state = kzalloc(sizeof(*state) + arr_size, GFP_KERNEL);
+ state = devm_kzalloc(&pdev->dev, sizeof(*state) + arr_size, GFP_KERNEL);
if (!state)
return -ENOMEM;

@@ -234,9 +234,11 @@ static int gpio_flash_probe(struct platform_device *pdev)
state->map.copy_to = gf_copy_to;
state->map.bankwidth = pdata->width;
state->map.size = state->win_size * (1 << state->gpio_count);
- state->map.virt = ioremap_nocache(memory->start, state->win_size);
- if (!state->map.virt)
- return -ENOMEM;
+ state->map.virt = devm_ioremap_resource(&pdev->dev, memory);
+ if (IS_ERR(state->map.virt)) {
+ dev_err(&pdev->dev, "failed to map memory\n");
+ return PTR_ERR(state->map.virt);
+ }

state->map.phys = NO_XIP;
state->map.map_priv_1 = (unsigned long)state;
@@ -245,12 +247,10 @@ static int gpio_flash_probe(struct platform_device *pdev)

i = 0;
do {
- if (gpio_request(state->gpio_addrs[i], DRIVER_NAME)) {
+ if (devm_gpio_request(&pdev->dev, state->gpio_addrs[i],
+ DRIVER_NAME)) {
dev_err(&pdev->dev, "failed to request gpio %d\n",
state->gpio_addrs[i]);
- while (i--)
- gpio_free(state->gpio_addrs[i]);
- kfree(state);
return -EBUSY;
}
gpio_direction_output(state->gpio_addrs[i], 0);
@@ -259,12 +259,8 @@ static int gpio_flash_probe(struct platform_device *pdev)
dev_notice(&pdev->dev, "probing %d-bit flash bus\n",
state->map.bankwidth * 8);
state->mtd = do_map_probe(memory->name, &state->map);
- if (!state->mtd) {
- for (i = 0; i < state->gpio_count; ++i)
- gpio_free(state->gpio_addrs[i]);
- kfree(state);
+ if (!state->mtd)
return -ENXIO;
- }
state->mtd->dev.parent = &pdev->dev;

mtd_device_parse_register(state->mtd, part_probe_types, NULL,
@@ -276,13 +272,9 @@ static int gpio_flash_probe(struct platform_device *pdev)
static int gpio_flash_remove(struct platform_device *pdev)
{
struct async_state *state = platform_get_drvdata(pdev);
- size_t i = 0;
- do {
- gpio_free(state->gpio_addrs[i]);
- } while (++i < state->gpio_count);
+
mtd_device_unregister(state->mtd);
map_destroy(state->mtd);
- kfree(state);
return 0;
}

--
2.18.0


2018-08-21 14:33:27

by Ricardo Ribalda Delgado

[permalink] [raw]
Subject: [PATCH 4/8] mtd: maps: gpio-addr-flash: Use order insted of size

By using the order of the window instead of the size, we can replace a
lot of expensive division and modulus on the code with simple bit
operations.

Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
---
drivers/mtd/maps/gpio-addr-flash.c | 39 ++++++++++++++++--------------
1 file changed, 21 insertions(+), 18 deletions(-)

diff --git a/drivers/mtd/maps/gpio-addr-flash.c b/drivers/mtd/maps/gpio-addr-flash.c
index 54a0d7d2365a..22e100f07112 100644
--- a/drivers/mtd/maps/gpio-addr-flash.c
+++ b/drivers/mtd/maps/gpio-addr-flash.c
@@ -25,6 +25,8 @@
#include <linux/slab.h>
#include <linux/types.h>

+#define win_mask(x) ((BIT(x)) - 1)
+
#define DRIVER_NAME "gpio-addr-flash"

/**
@@ -34,7 +36,7 @@
* @gpio_count: number of GPIOs used to address
* @gpio_addrs: array of GPIOs to twiddle
* @gpio_values: cached GPIO values
- * @win_size: dedicated memory size (if no GPIOs)
+ * @win_order: dedicated memory size (if no GPIOs)
*/
struct async_state {
struct mtd_info *mtd;
@@ -42,7 +44,7 @@ struct async_state {
size_t gpio_count;
unsigned *gpio_addrs;
int *gpio_values;
- unsigned long win_size;
+ unsigned int win_order;
};
#define gf_map_info_to_state(mi) ((struct async_state *)(mi)->map_priv_1)

@@ -60,7 +62,8 @@ static void gf_set_gpios(struct async_state *state, unsigned long ofs)
{
size_t i = 0;
int value;
- ofs /= state->win_size;
+
+ ofs >>= state->win_order;
do {
value = ofs & (1 << i);
if (state->gpio_values[i] != value) {
@@ -83,7 +86,7 @@ static map_word gf_read(struct map_info *map, unsigned long ofs)

gf_set_gpios(state, ofs);

- word = readw(map->virt + (ofs % state->win_size));
+ word = readw(map->virt + (ofs & win_mask(state->win_order)));
test.x[0] = word;
return test;
}
@@ -105,14 +108,14 @@ static void gf_copy_from(struct map_info *map, void *to, unsigned long from, ssi
int this_len;

while (len) {
- if ((from % state->win_size) + len > state->win_size)
- this_len = state->win_size - (from % state->win_size);
- else
- this_len = len;
+ this_len = from & win_mask(state->win_order);
+ this_len = BIT(state->win_order) - this_len;
+ this_len = min_t(int, len, this_len);

gf_set_gpios(state, from);
- memcpy_fromio(to, map->virt + (from % state->win_size),
- this_len);
+ memcpy_fromio(to,
+ map->virt + (from & win_mask(state->win_order)),
+ this_len);
len -= this_len;
from += this_len;
to += this_len;
@@ -132,7 +135,7 @@ static void gf_write(struct map_info *map, map_word d1, unsigned long ofs)
gf_set_gpios(state, ofs);

d = d1.x[0];
- writew(d, map->virt + (ofs % state->win_size));
+ writew(d, map->virt + (ofs & win_mask(state->win_order)));
}

/**
@@ -152,13 +155,13 @@ static void gf_copy_to(struct map_info *map, unsigned long to,
int this_len;

while (len) {
- if ((to % state->win_size) + len > state->win_size)
- this_len = state->win_size - (to % state->win_size);
- else
- this_len = len;
+ this_len = to & win_mask(state->win_order);
+ this_len = BIT(state->win_order) - this_len;
+ this_len = min_t(int, len, this_len);

gf_set_gpios(state, to);
- memcpy_toio(map->virt + (to % state->win_size), from, len);
+ memcpy_toio(map->virt + (to & win_mask(state->win_order)),
+ from, len);

len -= this_len;
to += this_len;
@@ -224,7 +227,7 @@ static int gpio_flash_probe(struct platform_device *pdev)
state->gpio_count = gpios->end;
state->gpio_addrs = (void *)(unsigned long)gpios->start;
state->gpio_values = (void *)(state + 1);
- state->win_size = resource_size(memory);
+ state->win_order = get_bitmask_order(resource_size(memory)) - 1;
memset(state->gpio_values, 0xff, arr_size);

state->map.name = DRIVER_NAME;
@@ -233,7 +236,7 @@ static int gpio_flash_probe(struct platform_device *pdev)
state->map.write = gf_write;
state->map.copy_to = gf_copy_to;
state->map.bankwidth = pdata->width;
- state->map.size = state->win_size * (1 << state->gpio_count);
+ state->map.size = BIT(state->win_order + state->gpio_count);
state->map.virt = devm_ioremap_resource(&pdev->dev, memory);
if (IS_ERR(state->map.virt)) {
dev_err(&pdev->dev, "failed to map memory\n");
--
2.18.0


2018-08-21 14:33:41

by Ricardo Ribalda Delgado

[permalink] [raw]
Subject: [PATCH 5/8] mtd: maps: gpio-addr-flash: Replace array with an integer

By replacing the array with an integer we can avoid completely
the bit comparison loop if the value has not changed (by far
the most common case).

Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
---
drivers/mtd/maps/gpio-addr-flash.c | 31 +++++++++++++++---------------
1 file changed, 16 insertions(+), 15 deletions(-)

diff --git a/drivers/mtd/maps/gpio-addr-flash.c b/drivers/mtd/maps/gpio-addr-flash.c
index 22e100f07112..8f5e3dce9be3 100644
--- a/drivers/mtd/maps/gpio-addr-flash.c
+++ b/drivers/mtd/maps/gpio-addr-flash.c
@@ -43,7 +43,7 @@ struct async_state {
struct map_info map;
size_t gpio_count;
unsigned *gpio_addrs;
- int *gpio_values;
+ unsigned int gpio_values;
unsigned int win_order;
};
#define gf_map_info_to_state(mi) ((struct async_state *)(mi)->map_priv_1)
@@ -55,22 +55,25 @@ struct async_state {
*
* Rather than call the GPIO framework every time, cache the last-programmed
* value. This speeds up sequential accesses (which are by far the most common
- * type). We rely on the GPIO framework to treat non-zero value as high so
- * that we don't have to normalize the bits.
+ * type).
*/
static void gf_set_gpios(struct async_state *state, unsigned long ofs)
{
- size_t i = 0;
- int value;
+ int i;

ofs >>= state->win_order;
- do {
- value = ofs & (1 << i);
- if (state->gpio_values[i] != value) {
- gpio_set_value(state->gpio_addrs[i], value);
- state->gpio_values[i] = value;
- }
- } while (++i < state->gpio_count);
+
+ if (ofs == state->gpio_values)
+ return;
+
+ for (i = 0; i < state->gpio_count; i++) {
+ if ((ofs & BIT(i)) == (state->gpio_values & BIT(i)))
+ continue;
+
+ gpio_set_value(state->gpio_addrs[i], !!(ofs & BIT(i)));
+ }
+
+ state->gpio_values = ofs;
}

/**
@@ -215,7 +218,7 @@ static int gpio_flash_probe(struct platform_device *pdev)
if (!memory || !gpios || !gpios->end)
return -EINVAL;

- arr_size = sizeof(int) * gpios->end;
+ arr_size = sizeof(state->gpio_addrs[0]) * gpios->end;
state = devm_kzalloc(&pdev->dev, sizeof(*state) + arr_size, GFP_KERNEL);
if (!state)
return -ENOMEM;
@@ -226,9 +229,7 @@ static int gpio_flash_probe(struct platform_device *pdev)
*/
state->gpio_count = gpios->end;
state->gpio_addrs = (void *)(unsigned long)gpios->start;
- state->gpio_values = (void *)(state + 1);
state->win_order = get_bitmask_order(resource_size(memory)) - 1;
- memset(state->gpio_values, 0xff, arr_size);

state->map.name = DRIVER_NAME;
state->map.read = gf_read;
--
2.18.0


2018-08-21 14:33:51

by Ricardo Ribalda Delgado

[permalink] [raw]
Subject: [PATCH 7/8] mtd: maps: gpio-addr-flash: Add support for device-tree devices

Allow creating gpio-addr-flash via device-tree and not just via platform
data.

The gpio probing has been moved to a different function allowing
deferred probing if they are not ready.

Option parsing has been also moved to separated functions.

Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
---
drivers/mtd/maps/gpio-addr-flash.c | 187 +++++++++++++++++++++++------
1 file changed, 148 insertions(+), 39 deletions(-)

diff --git a/drivers/mtd/maps/gpio-addr-flash.c b/drivers/mtd/maps/gpio-addr-flash.c
index 9455a8448064..b44011987137 100644
--- a/drivers/mtd/maps/gpio-addr-flash.c
+++ b/drivers/mtd/maps/gpio-addr-flash.c
@@ -7,6 +7,7 @@
*
* Copyright © 2000 Nicolas Pitre <[email protected]>
* Copyright © 2005-2009 Analog Devices Inc.
+ * Copyright © 2018 Ricardo Ribalda <[email protected]>
*
* Enter bugs at http://blackfin.uclinux.org/
*
@@ -24,6 +25,7 @@
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/types.h>
+#include <linux/of_gpio.h>

#define win_mask(x) ((BIT(x)) - 1)

@@ -172,8 +174,122 @@ static void gf_copy_to(struct map_info *map, unsigned long to,
}
}

-static const char * const part_probe_types[] = {
- "cmdlinepart", "RedBoot", NULL };
+static int gf_bankwidth(struct platform_device *pdev)
+{
+ struct device_node *dn;
+ int ret;
+ u32 bankwidth;
+
+ dn = pdev->dev.of_node;
+ if (!dn) {
+ struct physmap_flash_data *pdata;
+
+ pdata = dev_get_platdata(&pdev->dev);
+ return pdata->width;
+ }
+
+ ret = of_property_read_u32(dn, "bank-width", &bankwidth);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to get bank-width\n");
+ return -EINVAL;
+ }
+
+ return bankwidth;
+}
+
+static const char *gf_probe_type(struct platform_device *pdev)
+{
+ struct device_node *dn;
+ struct resource *memory;
+ const char *of_probe;
+
+ dn = pdev->dev.of_node;
+ if (!dn) {
+ memory = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ return memory->name;
+ }
+
+ of_probe = of_get_property(dn, "probe-type", NULL);
+ if (of_probe)
+ return of_probe;
+
+ return "cfi_probe";
+}
+
+static void gf_device_parse_register(struct platform_device *pdev,
+ struct async_state *state)
+{
+ static const char * const part_probe_types[] = {
+ "cmdlinepart", "RedBoot", "ofpart", "ofoldpart", NULL };
+ struct device_node *dn;
+
+ dn = pdev->dev.of_node;
+ if (!dn) {
+ struct physmap_flash_data *pdata;
+
+ pdata = dev_get_platdata(&pdev->dev);
+ mtd_device_parse_register(state->mtd, part_probe_types, NULL,
+ pdata->parts, pdata->nr_parts);
+ return;
+ }
+
+ mtd_device_parse_register(state->mtd, part_probe_types, NULL, NULL, 0);
+}
+
+static int gpio_flash_probe_gpios(struct platform_device *pdev,
+ struct async_state *state)
+{
+ struct physmap_flash_data *pdata;
+ struct device_node *dn;
+ struct resource *gpios;
+ int i;
+
+ dn = pdev->dev.of_node;
+ if (!dn) {
+ pdata = dev_get_platdata(&pdev->dev);
+ if (!pdata)
+ return -EINVAL;
+ gpios = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (IS_ERR(gpios) || !gpios->end)
+ return -EINVAL;
+ }
+
+ if (dn)
+ state->gpio_count = of_gpio_count(dn);
+ else
+ state->gpio_count = gpios->end;
+
+ state->gpio_addrs = devm_kzalloc(&pdev->dev,
+ sizeof(state->gpio_addrs[0])
+ * state->gpio_count,
+ GFP_KERNEL);
+ if (!state->gpio_addrs)
+ return -ENOMEM;
+
+ for (i = 0; i < state->gpio_count; i++) {
+ int gpio, ret;
+
+ if (dn)
+ gpio = of_get_gpio(dn, i);
+ else
+ gpio = ((unsigned long *)gpios->start)[i];
+
+ if (gpio < 0)
+ return gpio;
+
+ ret = devm_gpio_request(&pdev->dev, gpio, DRIVER_NAME);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to request gpio %d\n",
+ gpio);
+ return ret;
+ }
+ state->gpio_addrs[i] = gpio;
+ gpio_direction_output(state->gpio_addrs[i], 0);
+ }
+
+ return 0;
+}
+

/**
* gpio_flash_probe() - setup a mapping for a GPIO assisted flash
@@ -205,74 +321,58 @@ static const char * const part_probe_types[] = {
*/
static int gpio_flash_probe(struct platform_device *pdev)
{
- size_t i;
- struct physmap_flash_data *pdata;
struct resource *memory;
- struct resource *gpios;
struct async_state *state;
+ int ret;

- pdata = dev_get_platdata(&pdev->dev);
memory = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- gpios = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-
- if (!memory || !gpios || !gpios->end)
+ if (!memory)
return -EINVAL;

+ if (!is_power_of_2(resource_size(memory))) {
+ dev_err(&pdev->dev, "Window size must be aligned\n");
+ return -EIO;
+ }
+
state = devm_kzalloc(&pdev->dev, sizeof(*state), GFP_KERNEL);
if (!state)
return -ENOMEM;
+ platform_set_drvdata(pdev, state);

- /*
- * We cast start/end to known types in the boards file, so cast
- * away their pointer types here to the known types (gpios->xxx).
- */
- state->gpio_count = gpios->end;
- state->gpio_addrs = devm_kzalloc(&pdev->dev,
- sizeof(state->gpio_addrs[0]) *
- gpios->end,
- GFP_KERNEL);
- if (!state->gpio_addrs)
- return -ENOMEM;
- state->win_order = get_bitmask_order(resource_size(memory)) - 1;
+ ret = gpio_flash_probe_gpios(pdev, state);
+ if (ret < 0)
+ return ret;

+ state->win_order = get_bitmask_order(resource_size(memory)) - 1;
state->map.name = DRIVER_NAME;
state->map.read = gf_read;
state->map.copy_from = gf_copy_from;
state->map.write = gf_write;
state->map.copy_to = gf_copy_to;
- state->map.bankwidth = pdata->width;
+
+ ret = gf_bankwidth(pdev);
+ if (ret < 0)
+ return ret;
+ state->map.bankwidth = ret;
+
state->map.size = BIT(state->win_order + state->gpio_count);
state->map.virt = devm_ioremap_resource(&pdev->dev, memory);
if (IS_ERR(state->map.virt)) {
dev_err(&pdev->dev, "failed to map memory\n");
return PTR_ERR(state->map.virt);
}
-
state->map.phys = NO_XIP;
state->map.map_priv_1 = (unsigned long)state;

- platform_set_drvdata(pdev, state);
-
- i = 0;
- do {
- if (devm_gpio_request(&pdev->dev, state->gpio_addrs[i],
- DRIVER_NAME)) {
- dev_err(&pdev->dev, "failed to request gpio %d\n",
- state->gpio_addrs[i]);
- return -EBUSY;
- }
- gpio_direction_output(state->gpio_addrs[i], 0);
- } while (++i < state->gpio_count);
-
dev_notice(&pdev->dev, "probing %d-bit flash bus\n",
state->map.bankwidth * 8);
- state->mtd = do_map_probe(memory->name, &state->map);
+ state->mtd = do_map_probe(gf_probe_type(pdev), &state->map);
if (!state->mtd)
return -ENXIO;
state->mtd->dev.parent = &pdev->dev;
+ mtd_set_of_node(state->mtd, pdev->dev.of_node);

- mtd_device_parse_register(state->mtd, part_probe_types, NULL,
- pdata->parts, pdata->nr_parts);
+ gf_device_parse_register(pdev, state);

return 0;
}
@@ -286,11 +386,20 @@ static int gpio_flash_remove(struct platform_device *pdev)
return 0;
}

+static const struct of_device_id gpio_flash_match[] = {
+ {
+ .compatible = "cfi-gpio-addr-flash",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, gpio_flash_match);
+
static struct platform_driver gpio_flash_driver = {
.probe = gpio_flash_probe,
.remove = gpio_flash_remove,
.driver = {
.name = DRIVER_NAME,
+ .of_match_table = gpio_flash_match,
},
};

--
2.18.0


2018-08-21 16:05:44

by Ricardo Ribalda Delgado

[permalink] [raw]
Subject: [PATCH 6/8] mtd: maps: gpio-addr-flash: Split allocation in two

Instead of making one allocation and then calculating the addresses of
those two pointers in that area make two allocations. This simplifies
the code.

Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
---
drivers/mtd/maps/gpio-addr-flash.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/mtd/maps/gpio-addr-flash.c b/drivers/mtd/maps/gpio-addr-flash.c
index 8f5e3dce9be3..9455a8448064 100644
--- a/drivers/mtd/maps/gpio-addr-flash.c
+++ b/drivers/mtd/maps/gpio-addr-flash.c
@@ -205,7 +205,7 @@ static const char * const part_probe_types[] = {
*/
static int gpio_flash_probe(struct platform_device *pdev)
{
- size_t i, arr_size;
+ size_t i;
struct physmap_flash_data *pdata;
struct resource *memory;
struct resource *gpios;
@@ -218,8 +218,7 @@ static int gpio_flash_probe(struct platform_device *pdev)
if (!memory || !gpios || !gpios->end)
return -EINVAL;

- arr_size = sizeof(state->gpio_addrs[0]) * gpios->end;
- state = devm_kzalloc(&pdev->dev, sizeof(*state) + arr_size, GFP_KERNEL);
+ state = devm_kzalloc(&pdev->dev, sizeof(*state), GFP_KERNEL);
if (!state)
return -ENOMEM;

@@ -228,7 +227,12 @@ static int gpio_flash_probe(struct platform_device *pdev)
* away their pointer types here to the known types (gpios->xxx).
*/
state->gpio_count = gpios->end;
- state->gpio_addrs = (void *)(unsigned long)gpios->start;
+ state->gpio_addrs = devm_kzalloc(&pdev->dev,
+ sizeof(state->gpio_addrs[0]) *
+ gpios->end,
+ GFP_KERNEL);
+ if (!state->gpio_addrs)
+ return -ENOMEM;
state->win_order = get_bitmask_order(resource_size(memory)) - 1;

state->map.name = DRIVER_NAME;
--
2.18.0


2018-08-21 16:06:11

by Ricardo Ribalda Delgado

[permalink] [raw]
Subject: [PATCH 8/8] dt-binding: mtd: Document gpio-addr-flash

Add documentation for gpio-addr-flash. This binding allow creating
flash devices that are paged using GPIOs.

Cc: [email protected]
Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
---
.../bindings/mtd/gpio-addr-flash.txt | 46 +++++++++++++++++++
1 file changed, 46 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt

diff --git a/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt b/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt
new file mode 100644
index 000000000000..4279e8cad09b
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt
@@ -0,0 +1,46 @@
+Memory Mapped flash with some address lines addressed using GPIOs
+
+Handle the case where a flash device is mostly addressed using physical
+line and supplemented by GPIOs. This way you can hook up say a 8MiB flash
+to a 2MiB memory range and use the GPIOs to select a particular range.
+
+ - compatible : "cfi-gpio-addr-flash"
+ - reg : Address range of the mtd chip that is memory mapped, this is,
+ on the previous example 2MiB.
+ - bank-width : Width (in bytes) of the bank. Equal to the
+ device width times the number of interleaved chips.
+ - probe-type : (optional) "cfi_probe", "jedec_probe". How the mtd chip
+ is going to be probed. If omitted, assumed to be equal to "cfi_probe".
+ - #address-cells, #size-cells : Must be present if the device has
+ sub-nodes representing partitions (see below). In this case
+ both #address-cells and #size-cells must be equal to 1.
+
+The device tree may optionally contain sub-nodes describing partitions of the
+address space. See partition.txt for more detail.
+
+Example:
+
+ cfi_flash_0: cfi_flash {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "cfi-gpio-addr-flash";
+ bank-width = <2>;
+ reg = < 0x00300000 0x00200000 >;
+ gpios = <&gpio_0 3 0>, <&gpio_0 4 0>;
+ partition@0 {
+ reg = < 0x0 0x200000 >;
+ label = "Golden Bitstream";
+ };
+ partition@200000 {
+ reg = < 0x200000 0x200000 >;
+ label = "User Bitstream";
+ };
+ partition@400000 {
+ reg = < 0x400000 0x200000 >;
+ label = "V4L Controls";
+ };
+ partition@600000 {
+ reg = < 0x600000 0x200000 >;
+ label = "Production Data";
+ };
+ } ;
--
2.18.0


2018-08-21 16:16:57

by Ricardo Ribalda Delgado

[permalink] [raw]
Subject: [PATCH 1/8] mtd: maps: gpio-addr-flash: Replace custom printk

Use preferred print methods dev_*

Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
---
drivers/mtd/maps/gpio-addr-flash.c | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/drivers/mtd/maps/gpio-addr-flash.c b/drivers/mtd/maps/gpio-addr-flash.c
index 9d9723693217..17be47f72973 100644
--- a/drivers/mtd/maps/gpio-addr-flash.c
+++ b/drivers/mtd/maps/gpio-addr-flash.c
@@ -25,11 +25,7 @@
#include <linux/slab.h>
#include <linux/types.h>

-#define pr_devinit(fmt, args...) \
- ({ static const char __fmt[] = fmt; printk(__fmt, ## args); })
-
#define DRIVER_NAME "gpio-addr-flash"
-#define PFX DRIVER_NAME ": "

/**
* struct async_state - keep GPIO flash state
@@ -250,7 +246,7 @@ static int gpio_flash_probe(struct platform_device *pdev)
i = 0;
do {
if (gpio_request(state->gpio_addrs[i], DRIVER_NAME)) {
- pr_devinit(KERN_ERR PFX "failed to request gpio %d\n",
+ dev_err(&pdev->dev, "failed to request gpio %d\n",
state->gpio_addrs[i]);
while (i--)
gpio_free(state->gpio_addrs[i]);
@@ -260,8 +256,8 @@ static int gpio_flash_probe(struct platform_device *pdev)
gpio_direction_output(state->gpio_addrs[i], 0);
} while (++i < state->gpio_count);

- pr_devinit(KERN_NOTICE PFX "probing %d-bit flash bus\n",
- state->map.bankwidth * 8);
+ dev_notice(&pdev->dev, "probing %d-bit flash bus\n",
+ state->map.bankwidth * 8);
state->mtd = do_map_probe(memory->name, &state->map);
if (!state->mtd) {
for (i = 0; i < state->gpio_count; ++i)
--
2.18.0


2018-08-28 14:27:55

by Boris Brezillon

[permalink] [raw]
Subject: Re: [PATCH 2/8] mtd: maps: gpio-addr-flash: Fix ioremapped size

On Tue, 21 Aug 2018 16:31:46 +0200
Ricardo Ribalda Delgado <[email protected]> wrote:

> We should only iomap the area of the chip that is memory mapped.
> Otherwise we could be mapping devices beyond the memory space or that
> belong to other devices.
>

Can you add

Fixes: ebd71e3a4861 ("mtd: maps: gpio-addr-flash: fix warnings and make more portable")

and in case you want to backport the fix:

Cc: <[email protected]>

> Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
> ---
> drivers/mtd/maps/gpio-addr-flash.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/mtd/maps/gpio-addr-flash.c b/drivers/mtd/maps/gpio-addr-flash.c
> index 17be47f72973..6de16e81994c 100644
> --- a/drivers/mtd/maps/gpio-addr-flash.c
> +++ b/drivers/mtd/maps/gpio-addr-flash.c
> @@ -234,7 +234,7 @@ static int gpio_flash_probe(struct platform_device *pdev)
> state->map.copy_to = gf_copy_to;
> state->map.bankwidth = pdata->width;
> state->map.size = state->win_size * (1 << state->gpio_count);
> - state->map.virt = ioremap_nocache(memory->start, state->map.size);
> + state->map.virt = ioremap_nocache(memory->start, state->win_size);
> if (!state->map.virt)
> return -ENOMEM;
>


2018-08-28 14:46:47

by Ricardo Ribalda Delgado

[permalink] [raw]
Subject: Re: [PATCH 2/8] mtd: maps: gpio-addr-flash: Fix ioremapped size

Hi Boris
On Tue, Aug 28, 2018 at 4:26 PM Boris Brezillon
<[email protected]> wrote:
>
> On Tue, 21 Aug 2018 16:31:46 +0200
> Ricardo Ribalda Delgado <[email protected]> wrote:
>
> > We should only iomap the area of the chip that is memory mapped.
> > Otherwise we could be mapping devices beyond the memory space or that
> > belong to other devices.
> >
>
> Can you add
>
> Fixes: ebd71e3a4861 ("mtd: maps: gpio-addr-flash: fix warnings and make more portable")


Sure, I have some other changes for the patchset at
https://github.com/ribalda/linux/tree/gpio-addr-flash-v2

I will wait a couple of days for more reviews and I will resend the patches


>
> and in case you want to backport the fix:
>
> Cc: <[email protected]>
>
> > Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
> > ---
> > drivers/mtd/maps/gpio-addr-flash.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/mtd/maps/gpio-addr-flash.c b/drivers/mtd/maps/gpio-addr-flash.c
> > index 17be47f72973..6de16e81994c 100644
> > --- a/drivers/mtd/maps/gpio-addr-flash.c
> > +++ b/drivers/mtd/maps/gpio-addr-flash.c
> > @@ -234,7 +234,7 @@ static int gpio_flash_probe(struct platform_device *pdev)
> > state->map.copy_to = gf_copy_to;
> > state->map.bankwidth = pdata->width;
> > state->map.size = state->win_size * (1 << state->gpio_count);
> > - state->map.virt = ioremap_nocache(memory->start, state->map.size);
> > + state->map.virt = ioremap_nocache(memory->start, state->win_size);
> > if (!state->map.virt)
> > return -ENOMEM;
> >
>


--
Ricardo Ribalda

2018-08-31 12:20:02

by Rob Herring (Arm)

[permalink] [raw]
Subject: Re: [PATCH 8/8] dt-binding: mtd: Document gpio-addr-flash

On Tue, Aug 21, 2018 at 04:31:52PM +0200, Ricardo Ribalda Delgado wrote:
> Add documentation for gpio-addr-flash. This binding allow creating
> flash devices that are paged using GPIOs.
>
> Cc: [email protected]
> Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
> ---
> .../bindings/mtd/gpio-addr-flash.txt | 46 +++++++++++++++++++
> 1 file changed, 46 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt
>
> diff --git a/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt b/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt
> new file mode 100644
> index 000000000000..4279e8cad09b
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt
> @@ -0,0 +1,46 @@
> +Memory Mapped flash with some address lines addressed using GPIOs

That's ugly...

> +
> +Handle the case where a flash device is mostly addressed using physical
> +line and supplemented by GPIOs. This way you can hook up say a 8MiB flash
> +to a 2MiB memory range and use the GPIOs to select a particular range.
> +
> + - compatible : "cfi-gpio-addr-flash"

Why a new compatible? Shouldn't just adding some address gpios to an
existing flash device binding be sufficient?

> + - reg : Address range of the mtd chip that is memory mapped, this is,
> + on the previous example 2MiB.
> + - bank-width : Width (in bytes) of the bank. Equal to the
> + device width times the number of interleaved chips.
> + - probe-type : (optional) "cfi_probe", "jedec_probe". How the mtd chip
> + is going to be probed. If omitted, assumed to be equal to "cfi_probe".
> + - #address-cells, #size-cells : Must be present if the device has
> + sub-nodes representing partitions (see below). In this case
> + both #address-cells and #size-cells must be equal to 1.
> +
> +The device tree may optionally contain sub-nodes describing partitions of the
> +address space. See partition.txt for more detail.
> +
> +Example:
> +
> + cfi_flash_0: cfi_flash {
> + #address-cells = <1>;
> + #size-cells = <1>;
> + compatible = "cfi-gpio-addr-flash";
> + bank-width = <2>;
> + reg = < 0x00300000 0x00200000 >;
> + gpios = <&gpio_0 3 0>, <&gpio_0 4 0>;
> + partition@0 {
> + reg = < 0x0 0x200000 >;
> + label = "Golden Bitstream";
> + };
> + partition@200000 {
> + reg = < 0x200000 0x200000 >;
> + label = "User Bitstream";
> + };
> + partition@400000 {
> + reg = < 0x400000 0x200000 >;
> + label = "V4L Controls";
> + };
> + partition@600000 {
> + reg = < 0x600000 0x200000 >;
> + label = "Production Data";
> + };
> + } ;
> --
> 2.18.0
>

2018-08-31 12:23:08

by Ricardo Ribalda Delgado

[permalink] [raw]
Subject: Re: [PATCH 8/8] dt-binding: mtd: Document gpio-addr-flash

aHi Robb
On Fri, Aug 31, 2018 at 2:17 PM Rob Herring <[email protected]> wrote:
>
> On Tue, Aug 21, 2018 at 04:31:52PM +0200, Ricardo Ribalda Delgado wrote:
> > Add documentation for gpio-addr-flash. This binding allow creating
> > flash devices that are paged using GPIOs.
> >
> > Cc: [email protected]
> > Signed-off-by: Ricardo Ribalda Delgado <[email protected]>
> > ---
> > .../bindings/mtd/gpio-addr-flash.txt | 46 +++++++++++++++++++
> > 1 file changed, 46 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt
> >
> > diff --git a/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt b/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt
> > new file mode 100644
> > index 000000000000..4279e8cad09b
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt
> > @@ -0,0 +1,46 @@
> > +Memory Mapped flash with some address lines addressed using GPIOs
>
> That's ugly...
>
If hw was perfect there would be no firmware engineers in the world :P

> > +
> > +Handle the case where a flash device is mostly addressed using physical
> > +line and supplemented by GPIOs. This way you can hook up say a 8MiB flash
> > +to a 2MiB memory range and use the GPIOs to select a particular range.
> > +
> > + - compatible : "cfi-gpio-addr-flash"
>
> Why a new compatible? Shouldn't just adding some address gpios to an
> existing flash device binding be sufficient?

Because today there are handled by two different drivers

Thanks!

>
> > + - reg : Address range of the mtd chip that is memory mapped, this is,
> > + on the previous example 2MiB.
> > + - bank-width : Width (in bytes) of the bank. Equal to the
> > + device width times the number of interleaved chips.
> > + - probe-type : (optional) "cfi_probe", "jedec_probe". How the mtd chip
> > + is going to be probed. If omitted, assumed to be equal to "cfi_probe".
> > + - #address-cells, #size-cells : Must be present if the device has
> > + sub-nodes representing partitions (see below). In this case
> > + both #address-cells and #size-cells must be equal to 1.
> > +
> > +The device tree may optionally contain sub-nodes describing partitions of the
> > +address space. See partition.txt for more detail.
> > +
> > +Example:
> > +
> > + cfi_flash_0: cfi_flash {
> > + #address-cells = <1>;
> > + #size-cells = <1>;
> > + compatible = "cfi-gpio-addr-flash";
> > + bank-width = <2>;
> > + reg = < 0x00300000 0x00200000 >;
> > + gpios = <&gpio_0 3 0>, <&gpio_0 4 0>;
> > + partition@0 {
> > + reg = < 0x0 0x200000 >;
> > + label = "Golden Bitstream";
> > + };
> > + partition@200000 {
> > + reg = < 0x200000 0x200000 >;
> > + label = "User Bitstream";
> > + };
> > + partition@400000 {
> > + reg = < 0x400000 0x200000 >;
> > + label = "V4L Controls";
> > + };
> > + partition@600000 {
> > + reg = < 0x600000 0x200000 >;
> > + label = "Production Data";
> > + };
> > + } ;
> > --
> > 2.18.0
> >



--
Ricardo Ribalda

2018-09-04 14:06:40

by Ricardo Ribalda Delgado

[permalink] [raw]
Subject: Re: [PATCH 0/8] gpio-addr-flash: Support for device-tree and cleanup

Hi!

Any other comment before I resubmit v2 tomorrow from
https://github.com/ribalda/linux/tree/gpio-addr-flash-v2

So far the diff for v2 I have

From Boris Brezillon:
-Add Fixes and cc:stable

From kbuild:
- Fix warnings

- Rebase


Thanks!
On Tue, Aug 21, 2018 at 4:31 PM Ricardo Ribalda Delgado
<[email protected]> wrote:
>
> This patch series does the following:
>
> 1) Fix bug regarding ioremap size
> 2) Cleanup code to use new APIs
> 3) Simplify numerical operations
> 4) Add support for device-tree devices
>
> Thanks!
>
> Ricardo Ribalda Delgado (8):
> mtd: maps: gpio-addr-flash: Replace custom printk
> mtd: maps: gpio-addr-flash: Fix ioremapped size
> mtd: maps: gpio-addr-flash: Use devm_* functions
> mtd: maps: gpio-addr-flash: Use order insted of size
> mtd: maps: gpio-addr-flash: Replace array with an integer
> mtd: maps: gpio-addr-flash: Split allocation in two
> mtd: maps: gpio-addr-flash: Add support for device-tree devices
> dt-binding: mtd: Document gpio-addr-flash
>
> .../bindings/mtd/gpio-addr-flash.txt | 46 +++
> drivers/mtd/maps/gpio-addr-flash.c | 277 ++++++++++++------
> 2 files changed, 237 insertions(+), 86 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/mtd/gpio-addr-flash.txt
>
> --
> 2.18.0
>


--
Ricardo Ribalda