Patch "pinctrl: sh-pfc: Add helper to handle bias lookup table" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

pinctrl: sh-pfc: Add helper to handle bias lookup table

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
pinctrl-sh-pfc-add-helper-to-handle-bias-lookup-table.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: =?UTF-8?q?Niklas=20S=C3=B6derlund?=
<[email protected]>
Date: Sat, 12 Nov 2016 17:04:25 +0100
Subject: pinctrl: sh-pfc: Add helper to handle bias lookup table
MIME-Version: 1.0
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Content-Transfer-Encoding: 8bit

From: Niklas Söderlund <[email protected]>

commit c314c9f15aa5f43f0e5c0e2602cc65798dbd1598 upstream.

On some SoC there are no simple mapping of pins to bias register bits and a lookup table is needed. This logic is already implemented in some SoC specific drivers that could benefit from a generic implementation.

Add helpers to deal with the lookup which later can be used by the SoC specific drivers. The logic used to lookup are different from the one it aims to replace, this is intentional. This new method reduces the memory consumption at the cost of increased CPU usage and fix a bug where a WARN() would incorrectly be triggered if the register offset is 0.

---
 drivers/pinctrl/sh-pfc/core.c   |   15 +++++++++++++++
 drivers/pinctrl/sh-pfc/core.h   |    4 ++++
 drivers/pinctrl/sh-pfc/sh_pfc.h |    6 ++++++
 3 files changed, 25 insertions(+)

@@ -389,6 +389,21 @@ int sh_pfc_config_mux(struct sh_pfc *pfc
 	return 0;
 }
 
+const struct sh_pfc_bias_info *
+sh_pfc_pin_to_bias_info(const struct sh_pfc_bias_info *info,
+			unsigned int num, unsigned int pin)
+{
+	unsigned int i;
+
+	for (i = 0; i < num; i++)
+		if (info[i].pin == pin)
+			return &info[i];
+
+	WARN_ONCE(1, "Pin %u is not in bias info list\n", pin);
+
+	return NULL;
+}
+
 static int sh_pfc_init_ranges(struct sh_pfc *pfc)
 {
 	struct sh_pfc_pin_range *range;

@@ -33,4 +33,8 @@ void sh_pfc_write_reg(struct sh_pfc *pfc
 int sh_pfc_get_pin_index(struct sh_pfc *pfc, unsigned int pin);
 int sh_pfc_config_mux(struct sh_pfc *pfc, unsigned mark, int pinmux_type);
 
+const struct sh_pfc_bias_info *
+sh_pfc_pin_to_bias_info(const struct sh_pfc_bias_info *info,
+			unsigned int num, unsigned int pin);
+
 #endif /* __SH_PFC_CORE_H__ */

@@ -189,6 +189,12 @@ struct sh_pfc_window {
 	unsigned long size;
 };
 
+struct sh_pfc_bias_info {
+	u16 pin;
+	u16 reg : 11;
+	u16 bit : 5;
+};
+
 struct sh_pfc_pin_range;
 
 struct sh_pfc {

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/pinctrl-sh-pfc-add-helper-to-handle-bias-lookup-table.patch queue-4.9/pinctrl-sh-pfc-r8a7795-use-lookup-function-for-bias-data.patch

Hi Greg,

Ah, you already found this was the missing dependency for "pinctrl: sh-pfc:
r8a7795: Use lookup function for bias data".
Sorry for not realizing that before.

BTW, if "/sys/kernel/debug/pinctrl/" falls under "user-visible" issues, you may want to add commit 5d7400c4acbf7fe6 ("pinctrl: sh-pfc: Do not unconditionally support PIN_CONFIG_BIAS_DISABLE"), too.

Thanks!

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds

Looks good, now queued up, thanks,

greg k-h