[PATCH v3 13/31] clk: mediatek: pll: Implement unregister API

Chen-Yu Tsai
2022-02-08T13:16:13Z

The PLL clk type within the MediaTek clk driver library only has a
register function, and no corresponding unregister function. This
means there is no way for its users to properly implement cleanup
and removal.

Add a matching unregister function for the PLL type clk.

Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: Miles Chen <miles.chen@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
---
drivers/clk/mediatek/clk-pll.c | 55 ++++++++++++++++++++++++++++++++++
drivers/clk/mediatek/clk-pll.h | 2 ++
2 files changed, 57 insertions(+)

diff --git a/drivers/clk/mediatek/clk-pll.c b/drivers/clk/mediatek/clk-pll.c
index 64f59554bc9b..b54e33b75d4e 100644
--- a/drivers/clk/mediatek/clk-pll.c
+++ b/drivers/clk/mediatek/clk-pll.c
@@ -360,6 +360,21 @@ static struct clk *mtk_clk_register_pll(const struct mtk_pll_data *data,
return clk;
}

+static void mtk_clk_unregister_pll(struct clk *clk)
+{
+ struct clk_hw *hw;
+ struct mtk_clk_pll *pll;
+
+ hw = __clk_get_hw(clk);
+ if (!hw)
+ return;
+
+ pll = to_mtk_clk_pll(hw);
+
+ clk_unregister(clk);
+ kfree(pll);
+}
+
void mtk_clk_register_plls(struct device_node *node,
const struct mtk_pll_data *plls, int num_plls, struct clk_onecell_data *clk_data)
{
@@ -388,4 +403,44 @@ void mtk_clk_register_plls(struct device_node *node,
}
EXPORT_SYMBOL_GPL(mtk_clk_register_plls);

+static __iomem void *mtk_clk_pll_get_base(struct clk *clk,
+ const struct mtk_pll_data *data)
+{
+ struct clk_hw *hw = __clk_get_hw(clk);
+ struct mtk_clk_pll *pll = to_mtk_clk_pll(hw);
+
+ return pll->base_addr - data->reg;
+}
+
+void mtk_clk_unregister_plls(const struct mtk_pll_data *plls, int num_plls,
+ struct clk_onecell_data *clk_data)
+{
+ __iomem void *base = NULL;
+ int i;
+
+ if (!clk_data)
+ return;
+
+ for (i = num_plls; i > 0; i--) {
+ const struct mtk_pll_data *pll = &plls[i - 1];
+
+ if (IS_ERR_OR_NULL(clk_data->clks[pll->id]))
+ continue;
+
+ /*
+ * This is quite ugly but unfortunately the clks don't have
+ * any device tied to them, so there's no place to store the
+ * pointer to the I/O region base address. We have to fetch
+ * it from one of the registered clks.
+ */
+ base = mtk_clk_pll_get_base(clk_data->clks[pll->id], pll);
+
+ mtk_clk_unregister_pll(clk_data->clks[pll->id]);
+ clk_data->clks[pll->id] = ERR_PTR(-ENOENT);
+ }
+
+ iounmap(base);
+}
+EXPORT_SYMBOL_GPL(mtk_clk_unregister_plls);
+
MODULE_LICENSE("GPL");
diff --git a/drivers/clk/mediatek/clk-pll.h b/drivers/clk/mediatek/clk-pll.h
index d01b0c38311d..a889b1e472e7 100644
--- a/drivers/clk/mediatek/clk-pll.h
+++ b/drivers/clk/mediatek/clk-pll.h
@@ -51,5 +51,7 @@ struct mtk_pll_data {
void mtk_clk_register_plls(struct device_node *node,
const struct mtk_pll_data *plls, int num_plls,
struct clk_onecell_data *clk_data);
+void mtk_clk_unregister_plls(const struct mtk_pll_data *plls, int num_plls,
+ struct clk_onecell_data *clk_data);

#endif /* __DRV_CLK_MTK_PLL_H */
--
2.35.0.263.gb82422642f-goog