clk: sunxi: add PLL5 and PLL6 support

Hello Dan,

[cc'ing Mike so he is aware of this too]

2014/1/9 Dan Carpenter [off-list ref]:

Hello Emilio L?pez,

The patch d584c1331d64: "clk: sunxi: add PLL5 and PLL6 support" from
Dec 23, 2013, leads to the Smatch following
static checker warning:
        drivers/clk/sunxi/clk-sunxi.c:952 sunxi_divs_clk_setup()
        error: buffer overflow 'clks' 2 <= 2

Thanks for reporting this.

drivers/clk/sunxi/clk-sunxi.c
   878          clks = kzalloc(SUNXI_DIVS_MAX_QTY * sizeof(struct clk *), GFP_KERNEL);
   879          if (!clks)
   880                  goto free_clkdata;
   881
   882          clk_data->clks = clks;
   883
   884          /* It's not a good idea to have automatic reparenting changing
   885           * our RAM clock! */
   886          clkflags = !strcmp("pll5", parent) ? 0 : CLK_SET_RATE_PARENT;
   887
   888          for (i = 0; i < SUNXI_DIVS_MAX_QTY; i++) {
   889                  if (of_property_read_string_index(node, "clock-output-names",
   890                                                    i, &clk_name) != 0)
   891                          break;

Presumably we will always hit this condition on the last iteration of
the loop, but I just wanted to confirm.
   892

[ snip ]

   947                  WARN_ON(IS_ERR(clk_data->clks[i]));
   948                  clk_register_clkdev(clks[i], clk_name, NULL);
   949          }
   950
   951          /* The last clock available on the getter is the parent */
   952          clks[i++] = pclk;
                ^^^^^^^^^^^^^^^^
Otherwise we overflow.

Indeed, it is very possible that we are overflowing here. I will send a 
patch to fix this as soon as possible; hopefully later today.

Thanks!

Emilio