In reply to mail: Holes management in syscon driver.
Hi Dong, Maxime, Lee, all,
Regmap also offers .rd_table and .wr_table structures that can be used to
specify valid ranges within agiven regmap configuration.
This patch uses these structures to declare holes in a syscon instance.
It takes the description from DT, and fills in the structures accordingly.
Can I have your opinion on this implementation ?
Thanks and Regards,
Seraphin
Seraphin Bonnaffe (2):
mfd: syscon: Document new DT binding "holes"
mfd: syscon: specify rd_table and wr_table from DT
Documentation/devicetree/bindings/mfd/syscon.txt | 5 ++++
drivers/mfd/syscon.c | 35 ++++++++++++++++++++++++
2 files changed, 40 insertions(+)
--
1.9.1
The syscon driver is based on regmap, which offers the possibility to
declare registers as readable/writable or not, thanks to rd_table and
wr_table.
This patch takes register map's holes description from DT, and fills in
the rd_table and wr_table of the corresponding syson instance accordingly.
Signed-off-by: Seraphin Bonnaffe <[email protected]>
---
drivers/mfd/syscon.c | 35 +++++++++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)
diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
index ca15878..2bfb45d 100644
--- a/drivers/mfd/syscon.c
+++ b/drivers/mfd/syscon.c
@@ -125,9 +125,15 @@ static int syscon_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct syscon_platform_data *pdata = dev_get_platdata(dev);
+ struct device_node *np = dev->of_node;
+ struct regmap_access_table *syscon_rw_table;
+ struct regmap_range *holes;
struct syscon *syscon;
struct resource *res;
void __iomem *base;
+ const __be32 *hole_prop;
+ u32 min, max, size;
+ u32 i, hlen, ngaps;
syscon = devm_kzalloc(dev, sizeof(*syscon), GFP_KERNEL);
if (!syscon)
@@ -141,6 +147,35 @@ static int syscon_probe(struct platform_device *pdev)
if (!base)
return -ENOMEM;
+ hole_prop = of_get_property(np, "holes", &hlen);
+ if (hole_prop) {
+ hlen /= sizeof(*hole_prop);
+ ngaps = hlen / 2;
+
+ holes = devm_kzalloc(dev, ngaps * sizeof(*holes), GFP_KERNEL);
+ if (!holes)
+ return -ENOMEM;
+
+ for (i = 0; i < ngaps; i++) {
+ min = (u32)of_read_number(&hole_prop[i * 2], 1);
+ size = (u32)of_read_number(&hole_prop[i * 2 + 1], 1);
+ max = min + size - 1;
+
+ holes[i].range_min = min;
+ holes[i].range_max = max;
+ }
+ syscon_rw_table = devm_kzalloc(dev, sizeof(*syscon_rw_table),
+ GFP_KERNEL);
+ if (!syscon_rw_table)
+ return -ENOMEM;
+
+ syscon_rw_table->no_ranges = holes;
+ syscon_rw_table->n_no_ranges = ngaps;
+
+ syscon_regmap_config.rd_table = syscon_rw_table;
+ syscon_regmap_config.wr_table = syscon_rw_table;
+ }
+
syscon_regmap_config.max_register = res->end - res->start - 3;
if (pdata)
syscon_regmap_config.name = pdata->label;
--
1.9.1
This patch adds DT bindings to declare holes in syscon register maps.
Signed-off-by: Seraphin Bonnaffe <[email protected]>
---
Documentation/devicetree/bindings/mfd/syscon.txt | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/Documentation/devicetree/bindings/mfd/syscon.txt b/Documentation/devicetree/bindings/mfd/syscon.txt
index fe8150b..80ab9ca 100644
--- a/Documentation/devicetree/bindings/mfd/syscon.txt
+++ b/Documentation/devicetree/bindings/mfd/syscon.txt
@@ -13,8 +13,13 @@ Required properties:
- compatible: Should contain "syscon".
- reg: the register region can be accessed from syscon
+Optional properties:
+- holes: Register regions that cannot be accessed within reg range.
+ Each hole is described with its offset address, followed by its size.
+
Examples:
gpr: iomuxc-gpr@020e0000 {
compatible = "fsl,imx6q-iomuxc-gpr", "syscon";
reg = <0x020e0000 0x38>;
+ holes = <0x000c 0x8 0x020 0x4>;
};
--
1.9.1
Hi Seraphin,
On 10/07/2014 03:22 PM, Seraphin Bonnaffe wrote:
> In reply to mail: Holes management in syscon driver.
>
> Hi Dong, Maxime, Lee, all,
>
> Regmap also offers .rd_table and .wr_table structures that can be used to
> specify valid ranges within agiven regmap configuration.
>
> This patch uses these structures to declare holes in a syscon instance.
> It takes the description from DT, and fills in the structures accordingly.
>
> Can I have your opinion on this implementation ?
As discussed face to face, it looks fine to me.
But we would like green light in the new "holes" property introduced.
Thanks,
Maxime
>
> Thanks and Regards,
> Seraphin
>
> Seraphin Bonnaffe (2):
> mfd: syscon: Document new DT binding "holes"
> mfd: syscon: specify rd_table and wr_table from DT
>
> Documentation/devicetree/bindings/mfd/syscon.txt | 5 ++++
> drivers/mfd/syscon.c | 35 ++++++++++++++++++++++++
> 2 files changed, 40 insertions(+)
>