[PATCH v4 10/15] pinctrl: make struct pinfunction a pointer in struct function_desc

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bartosz.golaszew...@linaro.org>

We currently duplicate the entire struct pinfunction object in
pinmux_generic_add_pinfunction(). While this is inevitable when the
arguments come in split through pinmux_generic_add_function(), users of
pinmux_generic_add_pinfunction() will typically pass addresses of
structures in .rodata, meaning we can try to avoid the duplication with
the help from kmemdup_const(). To that end: don't wrap the entire struct
pinfunction in struct function_desc but rather just store the address.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszew...@linaro.org>
---
 drivers/pinctrl/freescale/pinctrl-imx.c   |  2 +-
 drivers/pinctrl/mediatek/pinctrl-airoha.c |  2 +-
 drivers/pinctrl/mediatek/pinctrl-moore.c  |  2 +-
 drivers/pinctrl/pinctrl-ingenic.c         |  2 +-
 drivers/pinctrl/pinmux.c                  | 18 ++++++++++++++----
 drivers/pinctrl/pinmux.h                  |  2 +-
 6 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/drivers/pinctrl/freescale/pinctrl-imx.c 
b/drivers/pinctrl/freescale/pinctrl-imx.c
index 
9ed84479a5b43871861f46fe1326f1dfadc7f63c..0df7eba8ccd3209fbc4b2e67ffdea12b77b90858
 100644
--- a/drivers/pinctrl/freescale/pinctrl-imx.c
+++ b/drivers/pinctrl/freescale/pinctrl-imx.c
@@ -266,7 +266,7 @@ static int imx_pmx_set(struct pinctrl_dev *pctldev, 
unsigned selector,
        npins = grp->grp.npins;
 
        dev_dbg(ipctl->dev, "enable function %s group %s\n",
-               func->func.name, grp->grp.name);
+               func->func->name, grp->grp.name);
 
        for (i = 0; i < npins; i++) {
                /*
diff --git a/drivers/pinctrl/mediatek/pinctrl-airoha.c 
b/drivers/pinctrl/mediatek/pinctrl-airoha.c
index 
61aecc3555837ddada3bab9d7f28a6af7afdd3b3..33421dabaaac597382e75c4e5ab009390a2eb1e4
 100644
--- a/drivers/pinctrl/mediatek/pinctrl-airoha.c
+++ b/drivers/pinctrl/mediatek/pinctrl-airoha.c
@@ -2459,7 +2459,7 @@ static int airoha_pinmux_set_mux(struct pinctrl_dev 
*pctrl_dev,
                return -EINVAL;
 
        dev_dbg(pctrl_dev->dev, "enable function %s group %s\n",
-               desc->func.name, grp->grp.name);
+               desc->func->name, grp->grp.name);
 
        func = desc->data;
        for (i = 0; i < func->group_size; i++) {
diff --git a/drivers/pinctrl/mediatek/pinctrl-moore.c 
b/drivers/pinctrl/mediatek/pinctrl-moore.c
index 
17a08c73423fd089066e4894d2307c852bbbb661..11dc525eb3a2dc8ceabf2278ee1a2abaa425eec1
 100644
--- a/drivers/pinctrl/mediatek/pinctrl-moore.c
+++ b/drivers/pinctrl/mediatek/pinctrl-moore.c
@@ -56,7 +56,7 @@ static int mtk_pinmux_set_mux(struct pinctrl_dev *pctldev,
                return -EINVAL;
 
        dev_dbg(pctldev->dev, "enable function %s group %s\n",
-               func->func.name, grp->grp.name);
+               func->func->name, grp->grp.name);
 
        for (i = 0; i < grp->grp.npins; i++) {
                const struct mtk_pin_desc *desc;
diff --git a/drivers/pinctrl/pinctrl-ingenic.c 
b/drivers/pinctrl/pinctrl-ingenic.c
index 
e13ef07850386e70cffc83011589ceaf70a70a41..e5b24fab12e11e443df25ffeb7b70d7c1a03c6bc
 100644
--- a/drivers/pinctrl/pinctrl-ingenic.c
+++ b/drivers/pinctrl/pinctrl-ingenic.c
@@ -4015,7 +4015,7 @@ static int ingenic_pinmux_set_mux(struct pinctrl_dev 
*pctldev,
                return -EINVAL;
 
        dev_dbg(pctldev->dev, "enable function %s group %s\n",
-               func->func.name, grp->grp.name);
+               func->func->name, grp->grp.name);
 
        mode = (uintptr_t)grp->data;
        if (mode <= 3) {
diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c
index 
62bd4aa53b2b22cb09eacfb05398205f2fe391b9..6f5e3ede972bbfa78e279790df359632e2d63485
 100644
--- a/drivers/pinctrl/pinmux.c
+++ b/drivers/pinctrl/pinmux.c
@@ -810,7 +810,7 @@ pinmux_generic_get_function_name(struct pinctrl_dev 
*pctldev,
        if (!function)
                return NULL;
 
-       return function->func.name;
+       return function->func->name;
 }
 EXPORT_SYMBOL_GPL(pinmux_generic_get_function_name);
 
@@ -835,8 +835,8 @@ int pinmux_generic_get_function_groups(struct pinctrl_dev 
*pctldev,
                        __func__, selector);
                return -EINVAL;
        }
-       *groups = function->func.groups;
-       *ngroups = function->func.ngroups;
+       *groups = function->func->groups;
+       *ngroups = function->func->ngroups;
 
        return 0;
 }
@@ -903,7 +903,17 @@ int pinmux_generic_add_pinfunction(struct pinctrl_dev 
*pctldev,
        if (!function)
                return -ENOMEM;
 
-       function->func = *func;
+       /*
+        * FIXME: It's generally a bad idea to use devres in subsystem core
+        * code - managed interfaces are aimed at drivers - but pinctrl already
+        * uses it all over the place so it's a larger piece of technical debt
+        * to fix.
+        */
+       function->func = devm_kmemdup_const(pctldev->dev, func,
+                                           sizeof(*func), GFP_KERNEL);
+       if (!function->func)
+               return -ENOMEM;
+
        function->data = data;
 
        error = radix_tree_insert(&pctldev->pin_function_tree, selector, 
function);
diff --git a/drivers/pinctrl/pinmux.h b/drivers/pinctrl/pinmux.h
index 
549ab10f7afbda32fadf4ad151401180bed2064f..653684290666d78fd725febb5f8bc987b66a1afb
 100644
--- a/drivers/pinctrl/pinmux.h
+++ b/drivers/pinctrl/pinmux.h
@@ -137,7 +137,7 @@ static inline void pinmux_init_device_debugfs(struct dentry 
*devroot,
  * @data: pin controller driver specific data
  */
 struct function_desc {
-       struct pinfunction func;
+       const struct pinfunction *func;
        void *data;
 };
 

-- 
2.48.1