[PATCH] regulator: ti-abb: don't use devm_platform_ioremap_resource_byname for shared interrupt register

[Romain Naour]

From: Romain Naour <romain.naour@xxxxxxx>

We can't use devm_platform_ioremap_resource_byname() to remap the
interrupt register that can be shared between
regulator-abb-{ivahd,dspeve,gpu} drivers instance.

>From arm/boot/dts/dra7.dtsi:

The abb_mpu is the only instance using its own interrupt register:
  (0x4ae06014) PRM_IRQSTATUS_MPU_2, ABB_MPU_DONE_ST (bit 7)

The other tree instance (abb_ivahd, abb_dspeve, abb_gpu) share
PRM_IRQSTATUS_MPU register (0x4ae06010) but uses different bit
ABB_IVA_DONE_ST (bit 30), ABB_DSPEVE_DONE_ST( bit 29) and
ABB_GPU_DONE_ST (but 28).

The commit b36c6b1887ff (regulator: ti-abb: Make use of the helper
function devm_ioremap related) overlooked the following comment
explaining why devm_ioremap() is used in this case:

/*
 * We may have shared interrupt register offsets which are
 * write-1-to-clear between domains ensuring exclusivity.
 */

Fixes:
  [    1.326660] ti_abb 4ae07e30.regulator-abb-dspeve: can't request region for resource [mem 0x4ae06010-0x4ae06013]
  [    1.326660] ti_abb: probe of 4ae07e30.regulator-abb-dspeve failed with error -16
  [    1.327239] ti_abb 4ae07de4.regulator-abb-gpu: can't request region for resource [mem 0x4ae06010-0x4ae06013]
  [    1.327270] ti_abb: probe of 4ae07de4.regulator-abb-gpu failed with error -16

This partially reverts commit b36c6b1887ffc6b58b556120bfbd511880515247.

Signed-off-by: Romain Naour <romain.naour@xxxxxxx>
---
 drivers/regulator/ti-abb-regulator.c | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/drivers/regulator/ti-abb-regulator.c b/drivers/regulator/ti-abb-regulator.c
index f48214e2c3b4..21392b9261f4 100644
--- a/drivers/regulator/ti-abb-regulator.c
+++ b/drivers/regulator/ti-abb-regulator.c
@@ -726,9 +726,22 @@ static int ti_abb_probe(struct platform_device *pdev)
 			return PTR_ERR(abb->setup_reg);
 	}
 
-	abb->int_base = devm_platform_ioremap_resource_byname(pdev, "int-address");
-	if (IS_ERR(abb->int_base))
-		return PTR_ERR(abb->int_base);
+	pname = "int-address";
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, pname);
+	if (!res) {
+		dev_err(dev, "Missing '%s' IO resource\n", pname);
+		return -ENODEV;
+	}
+	/*
+	 * We may have shared interrupt register offsets which are
+	 * write-1-to-clear between domains ensuring exclusivity.
+	 */
+	abb->int_base = devm_ioremap(dev, res->start,
+					     resource_size(res));
+	if (!abb->int_base) {
+		dev_err(dev, "Unable to map '%s'\n", pname);
+		return -ENOMEM;
+	}
 
 	/* Map Optional resources */
 	pname = "efuse-address";
-- 
2.43.0