From mboxrd@z Thu Jan 1 00:00:00 1970 From: maxime.ripard@free-electrons.com (Maxime Ripard) Date: Sun, 7 Dec 2014 16:20:14 +0100 Subject: [PATCH 03/10] clk: sunxi: Add driver for A80 MMC config clocks/resets In-Reply-To: References: <1417588565-26215-1-git-send-email-wens@csie.org> <1417588565-26215-4-git-send-email-wens@csie.org> <20141206180144.GD12434@lukather> Message-ID: <20141207152014.GK12434@lukather> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sun, Dec 07, 2014 at 09:30:34AM +0800, Chen-Yu Tsai wrote: > > Having the either clk_prepare_enable (or clk_enable if you're in > > atomic context) in the assert/deassert seems more logical. > > I'll try it out and see if it works. Didn't work so well with the > USB clocks... If it doesn't, it would be good to know why, it really should work. > >> + ret = reset_control_deassert(data->reset); > >> + if (ret) { > >> + dev_err(&pdev->dev, "Reset deassert err %d\n", ret); > >> + goto err_reset; > >> + } > >> + > >> + for (i = 0; i < count; i++) { > >> + of_property_read_string_index(np, "clock-output-names", > >> + i, &clk_name); > >> + > >> + clk_data->clks[i] = clk_register_gate(&pdev->dev, clk_name, > >> + clk_parent, 0, > >> + data->membase + SUN9I_MMC_WIDTH * i, > >> + SUN9I_MMC_GATE_BIT, 0, > >> + &data->lock); > >> + > >> + if (IS_ERR(clk_data->clks[i])) { > >> + ret = PTR_ERR(clk_data->clks[i]); > >> + goto err_clk_register; > >> + } > >> + } > >> + > >> + ret = of_clk_add_provider(np, of_clk_src_onecell_get, clk_data); > >> + if (ret) > >> + goto err_clk_provider; > >> + > >> + data->rcdev.owner = THIS_MODULE; > >> + data->rcdev.nr_resets = count; > >> + data->rcdev.ops = &sun9i_mmc_reset_ops; > >> + data->rcdev.of_node = pdev->dev.of_node; > >> + > >> + ret = reset_controller_register(&data->rcdev); > >> + if (ret) > >> + goto err_rc_reg; > >> + > >> + platform_set_drvdata(pdev, data); > >> + > >> + return 0; > >> + > >> +err_rc_reg: > >> + of_clk_del_provider(np); > >> + > >> +err_clk_provider: > >> + for (i = 0; i < count; i++) > >> + clk_unregister(clk_data->clks[i]); > >> + > >> +err_clk_register: > >> + reset_control_assert(data->reset); > >> + > >> +err_reset: > >> + clk_disable_unprepare(data->clk); > >> + > >> + return ret; > >> +} > >> + > >> +static int sun9i_a80_mmc_clk_remove(struct platform_device *pdev) > >> +{ > >> + struct device_node *np = pdev->dev.of_node; > >> + struct sun9i_mmc_clk_data *data = platform_get_drvdata(pdev); > >> + struct clk_onecell_data *clk_data = &data->clk_data; > >> + int i; > >> + > >> + reset_controller_unregister(&data->rcdev); > >> + of_clk_del_provider(np); > >> + for (i = 0; i < clk_data->clk_num; i++) > >> + clk_unregister(clk_data->clks[i]); > >> + > >> + reset_control_assert(data->reset); > >> + clk_disable_unprepare(data->clk); > >> + > >> + return 0; > >> +} > >> + > >> +static const struct of_device_id sun9i_a80_mmc_clk_dt_ids[] = { > >> + { .compatible = "allwinner,sun9i-a80-mmc-clk" }, > >> + { /* sentinel */ } > >> +}; > >> + > >> +static struct platform_driver sun9i_a80_mmc_clk_driver = { > >> + .driver = { > >> + .name = "sun9i-a80-mmc-clk", > >> + .of_match_table = sun9i_a80_mmc_clk_dt_ids, > >> + }, > >> + .probe = sun9i_a80_mmc_clk_probe, > >> + .remove = sun9i_a80_mmc_clk_remove, > >> +}; > >> +module_platform_driver(sun9i_a80_mmc_clk_driver); > >> + > >> +MODULE_AUTHOR("Chen-Yu Tsai "); > >> +MODULE_DESCRIPTION("Allwinner A80 MMC clock/reset Driver"); > >> +MODULE_LICENSE("GPL v2"); > > > > What's the real benefit of enabling it as a platform driver? the reset > > framework is set up early enough that you can use OF_CLK_DECLARE. > > This clock/reset block also requires a reset control de-asserted. The > reset controllers are currently setup using platform devices. Are you > suggesting I use "allwinner,sun6i-a31-ahb1-reset" instead? That would > also imply having a .init_time callback for sun9i, and having > sun6i_reset_init() before of_clk_init(). Kind of confusing (not sure > this is the right word) for something not so critical. > > Also we get to use devres, but that's just a bonus. Ok, it makes sense then. Maxime -- Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: Digital signature URL: