[PATCH v3 06/15] mfd: bcm2835-pm: Use 'reg-names' to get resources

Nicolas Saenz Julienne
2021-02-17T11:53:36Z

If available in firmware, find resources by their 'reg-names' position
instead of relying on hardcoded offsets. Care is taken to support old
firmware nonetheless.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>

---

Changes since v2:
- correct names

drivers/mfd/bcm2835-pm.c | 55 ++++++++++++++++++++++++++--------------
1 file changed, 36 insertions(+), 19 deletions(-)

diff --git a/drivers/mfd/bcm2835-pm.c b/drivers/mfd/bcm2835-pm.c
index 42fe67f1538e..36fede92775c 100644
--- a/drivers/mfd/bcm2835-pm.c
+++ b/drivers/mfd/bcm2835-pm.c
@@ -25,9 +25,37 @@ static const struct mfd_cell bcm2835_power_devs[] = {
{ .name = "bcm2835-power" },
};

+static int bcm2835_pm_get_pdata(struct platform_device *pdev,
+ struct bcm2835_pm *pm)
+{
+ /* If no 'reg-names' property is found we can assume we're using old
+ * firmware.
+ */
+ if (!of_find_property(pm->dev->of_node, "reg-names", NULL)) {
+ dev_warn(pm->dev, "Old devicetree detected, please update your firmware.\n");
+
+ pm->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(pm->base))
+ return PTR_ERR(pm->base);
+
+ pm->asb = devm_platform_ioremap_resource(pdev, 1);
+ if (IS_ERR(pm->asb))
+ pm->asb = NULL;
+ } else {
+ pm->base = devm_platform_ioremap_resource_byname(pdev, "pm");
+ if (IS_ERR(pm->base))
+ return PTR_ERR(pm->base);
+
+ pm->asb = devm_platform_ioremap_resource_byname(pdev, "asb");
+ if (IS_ERR(pm->base))
+ pm->asb = NULL;
+ }
+
+ return 0;
+}
+
static int bcm2835_pm_probe(struct platform_device *pdev)
{
- struct resource *res;
struct device *dev = &pdev->dev;
struct bcm2835_pm *pm;
int ret;
@@ -39,10 +67,9 @@ static int bcm2835_pm_probe(struct platform_device *pdev)

pm->dev = dev;

- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- pm->base = devm_ioremap_resource(dev, res);
- if (IS_ERR(pm->base))
- return PTR_ERR(pm->base);
+ ret = bcm2835_pm_get_pdata(pdev, pm);
+ if (ret)
+ return ret;

ret = devm_mfd_add_devices(dev, -1,
bcm2835_pm_devs, ARRAY_SIZE(bcm2835_pm_devs),
@@ -54,20 +81,10 @@ static int bcm2835_pm_probe(struct platform_device *pdev)
* bcm2835-pm binding as the key for whether we can reference
* the full PM register range and support power domains.
*/
- res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
- if (res) {
- pm->asb = devm_ioremap_resource(dev, res);
- if (IS_ERR(pm->asb))
- return PTR_ERR(pm->asb);
-
- ret = devm_mfd_add_devices(dev, -1,
- bcm2835_power_devs,
- ARRAY_SIZE(bcm2835_power_devs),
- NULL, 0, NULL);
- if (ret)
- return ret;
- }
-
+ if (pm->asb)
+ return devm_mfd_add_devices(dev, -1, bcm2835_power_devs,
+ ARRAY_SIZE(bcm2835_power_devs),
+ NULL, 0, NULL);
return 0;
}

--
2.30.0