From patchwork Thu Oct 12 13:29:35 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Philipp Zabel X-Patchwork-Id: 10001977 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 8F9986028A for ; Thu, 12 Oct 2017 13:29:42 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7DE2F25F3E for ; Thu, 12 Oct 2017 13:29:42 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7291E283DA; Thu, 12 Oct 2017 13:29:42 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E929325F3E for ; Thu, 12 Oct 2017 13:29:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752838AbdJLN3l (ORCPT ); Thu, 12 Oct 2017 09:29:41 -0400 Received: from metis.ext.4.pengutronix.de ([92.198.50.35]:53923 "EHLO metis.ext.4.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752702AbdJLN3l (ORCPT ); Thu, 12 Oct 2017 09:29:41 -0400 Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7] helo=dude.pengutronix.de.) by metis.ext.pengutronix.de with esmtp (Exim 4.84_2) (envelope-from ) id 1e2dYR-0002RL-S4; Thu, 12 Oct 2017 15:29:39 +0200 From: Philipp Zabel To: linux-clk@vger.kernel.org Cc: Shawn Guo , Fabio Estevam , Michael Turquette , Stephen Boyd , linux-arm-kernel@lists.infradead.org, kernel@pengutronix.de, Philipp Zabel Subject: [PATCH] clk: imx: clk-imx6ul: allow lcdif_pre_sel to change parent rate Date: Thu, 12 Oct 2017 15:29:35 +0200 Message-Id: <20171012132935.3508-1-p.zabel@pengutronix.de> X-Mailer: git-send-email 2.11.0 X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: p.zabel@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-clk@vger.kernel.org Sender: linux-clk-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Allowing the lcdif_pre_sel to propagate rate changes to its parent PLL allows more fine grained control over the LCDIF pixel clock rate. For example, the Innovision AT043TN24 LCD panel described in the imx6ul-14x14-evk device tree requires a 9 MHz pixel clock. Before this patch, the lcdif_pre_sel clock rate is fixed, and just setting the lcdif_pred and lcdif_podf dividers only allows to get as close as about 8.44 MHz: pll3 1 1 480000000 0 0 pll3_bypass 1 1 480000000 0 0 pll3_usb_otg 1 1 480000000 0 0 pll3_pfd1_540m 1 1 540000000 0 0 lcdif_pre_sel 1 1 540000000 0 0 lcdif_pred 1 1 67500000 0 0 lcdif_podf 1 1 8437500 0 0 lcdif_pix 1 1 8437500 0 0 Once lcdif_pre_sel is allowed to propagate rate requests to its parent, the actual pixel clock matches the requested value: pll3 1 1 480000000 0 0 pll3_bypass 1 1 480000000 0 0 pll3_usb_otg 1 1 480000000 0 0 pll3_pfd1_540m 1 1 288000000 0 0 lcdif_pre_sel 1 1 288000000 0 0 lcdif_pred 1 1 36000000 0 0 lcdif_podf 1 1 9000000 0 0 lcdif_pix 1 1 9000000 0 0 Signed-off-by: Philipp Zabel Reviewed-by: Fabio Estevam --- drivers/clk/imx/clk-imx6ul.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/clk/imx/clk-imx6ul.c b/drivers/clk/imx/clk-imx6ul.c index 5e8c18afce9ad..85c1181644697 100644 --- a/drivers/clk/imx/clk-imx6ul.c +++ b/drivers/clk/imx/clk-imx6ul.c @@ -267,7 +267,7 @@ static void __init imx6ul_clocks_init(struct device_node *ccm_node) clks[IMX6ULL_CLK_EPDC_SEL] = imx_clk_mux("epdc_sel", base + 0x34, 9, 3, epdc_sels, ARRAY_SIZE(epdc_sels)); } clks[IMX6UL_CLK_ECSPI_SEL] = imx_clk_mux("ecspi_sel", base + 0x38, 18, 1, ecspi_sels, ARRAY_SIZE(ecspi_sels)); - clks[IMX6UL_CLK_LCDIF_PRE_SEL] = imx_clk_mux("lcdif_pre_sel", base + 0x38, 15, 3, lcdif_pre_sels, ARRAY_SIZE(lcdif_pre_sels)); + clks[IMX6UL_CLK_LCDIF_PRE_SEL] = imx_clk_mux_flags("lcdif_pre_sel", base + 0x38, 15, 3, lcdif_pre_sels, ARRAY_SIZE(lcdif_pre_sels), CLK_SET_RATE_PARENT); clks[IMX6UL_CLK_LCDIF_SEL] = imx_clk_mux("lcdif_sel", base + 0x38, 9, 3, lcdif_sels, ARRAY_SIZE(lcdif_sels)); clks[IMX6UL_CLK_LDB_DI0_DIV_SEL] = imx_clk_mux("ldb_di0", base + 0x20, 10, 1, ldb_di0_div_sels, ARRAY_SIZE(ldb_di0_div_sels));