Messages in this thread | | | Subject | Re: [PATCH v2 3/3] spi: meson-axg: add a linear clock divider support | From | Sunny Luo <> | Date | Thu, 13 Dec 2018 22:37:07 +0800 |
| |
Hi Jerome,
On 2018/12/13 17:28, Jerome Brunet wrote: > On Thu, 2018-12-13 at 09:55 +0100, Neil Armstrong wrote:
>>> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig >>> config SPI_MESON_SPICC >>> tristate "Amlogic Meson SPICC controller" >>> - depends on ARCH_MESON || COMPILE_TEST >>> + depends on OF && COMMON_CLK && (ARCH_MESON || COMPILE_TEST) > > The purpose of this patch is clock, right ? Why does it add a dependency on OF > ? > I did it by the way. Maybe it's better to add it in patch 1.
>>> +static int meson_spicc_clk_init(struct meson_spicc_device *spicc) >>> +{ >>> + struct device *dev = &spicc->pdev->dev; >>> + struct clk_fixed_factor *div0; >>> + struct clk_divider *div1; > > Could you come up with something better than div0 and div1 ? it is confusing, > especially with the comment above about div3 and 4 ... fixed_factor, div maybe > ? > Good, It is really confusing, I will change next patch.
>>> + div1 = &meson_spicc_div1; >>> + div1->reg = spicc->base + (u64)div1->reg; > > So you have static data which you override here. This works only if there is a > single instance ... and does not really improve readability in your case. > > IMO, you'd be better off without the static data above.
This is a terrible bug for more than one instances. I must overwrite it.
>>> + if (!spicc->data->has_enhance_clk_div) { > > Do all SoC with 'has_oen' have 'has_enhance_clk_div' too ? > DO you really need two flags ?
Yes, all Soc with 'has_oen' must have 'has_enhance_clk_div' too. It is distinct to use two flags here, what do you think of it?
>>> + mux = &meson_spicc_sel; >>> + snprintf(name, sizeof(name), "%s#_sel", dev_name(dev)); >>> + init.name = name; >>> + init.ops = &clk_mux_ops; >>> + init.parent_names = mux_parent_names; >>> + init.num_parents = 2; >>> + init.flags = CLK_SET_RATE_PARENT | CLK_SET_RATE_NO_REPARENT; > > Why CLK_SET_RATE_NO_REPARENT ? CCF should pick the parent that give the best > results, best to let it do its task ... > There are two div in AXG, one is the coarse old-div and the other is enhance-div. From SoCs designer's opinion, the ehance-div aims to take place of the old-div.
| |