clk: vc5: Add support for IDT VersaClock 5P49V5923 and 5P49V5933

Hello Marek Vasut,

The patch 3e1aec4e2c41: "clk: vc5: Add support for IDT VersaClock 5P49V5923 and 5P49V5933" from Jan 12, 2017, leads to the following static checker warning:

	drivers/clk/clk-versaclock5.c:235 vc5_mux_set_parent()
	error: uninitialized symbol 'src'.

drivers/clk/clk-versaclock5.c
210 static int vc5_mux_set_parent(struct clk_hw *hw, u8 index) 211 {
212 struct vc5_driver_data *vc5 =
213 container_of(hw, struct vc5_driver_data, clk_mux);
214 const u8 mask = VC5_PRIM_SRC_SHDN_EN_XTAL | VC5_PRIM_SRC_SHDN_EN_CLKIN;

   215          u8 src;
                   ^^^

216
217 if ((index > 1) || !vc5->clk_mux_ins)
218 return -EINVAL;
219
220 if (vc5->clk_mux_ins == (VC5_MUX_IN_CLKIN | VC5_MUX_IN_XIN)) {
221 if (index == 0)
222 src = VC5_PRIM_SRC_SHDN_EN_XTAL;
223 if (index == 1)
224 src = VC5_PRIM_SRC_SHDN_EN_CLKIN;
225 } else {
226 if (index != 0)
227 return -EINVAL;
228
229 if (vc5->clk_mux_ins == VC5_MUX_IN_XIN)
230 src = VC5_PRIM_SRC_SHDN_EN_XTAL;
231 if (vc5->clk_mux_ins == VC5_MUX_IN_CLKIN)
232 src = VC5_PRIM_SRC_SHDN_EN_CLKIN;

What about if both of these are false?

233 }
234

   235          return regmap_update_bits(vc5->regmap, VC5_PRIM_SRC_SHDN, mask, src);
                                                                                ^^^

Potentially uninitialized.

236 }

regards,
dan carpenter

Hi Dan,

That cannot happen, cfr. the initialization of clk_mux_ins.

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

Thanks.

I've figured out a way to fix Smatch so it doesn't complain about this particular warning in the future.

regards,
dan carpenter