Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753557AbaKHFbo (ORCPT ); Sat, 8 Nov 2014 00:31:44 -0500 Received: from va-smtp01.263.net ([54.88.144.211]:46542 "EHLO va-smtp01.263.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751561AbaKHFbm (ORCPT ); Sat, 8 Nov 2014 00:31:42 -0500 X-RL-SENDER: andy.yan@rock-chips.com X-FST-TO: airlied@linux.ie X-SENDER-IP: 127.0.0.1 X-LOGIN-NAME: andy.yan@rock-chips.com X-UNIQUE-TAG: <540f3e0a2398c1603d43f1ef738a8709> X-DNS-TYPE: 1 From: Andy Yan To: airlied@linux.ie, heiko@sntech.de, fabio.estevam@freescale.com, rmk+kernel@arm.linux.org.uk Cc: Greg Kroah-Hartman , Grant Likely , Rob Herring , Philipp Zabel , Shawn Guo , Andy yan , Josh Boyer , Sean Paul , Inki Dae , Dave Airlie , Arnd Bergmann , Lucas Stach , Zubair.Kakakhel@imgtec.com, djkurtz@google.com, ykk@rock-chips.com, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, devel@driverdev.osuosl.org, devicetree@vger.kernel.org, linux-rockchip@lists.infradead.org, jay.xu@rock-chips.com Subject: [PATCH V5 5/7] dw-hdmi: add support for multi byte register width access Date: Sat, 8 Nov 2014 13:31:06 +0800 Message-Id: <1415424666-7663-1-git-send-email-andy.yan@rock-chips.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1415424410-7364-1-git-send-email-andy.yan@rock-chips.com> References: <1415424410-7364-1-git-send-email-andy.yan@rock-chips.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On rockchip rk3288, only word(32-bit) accesses are permitted for hdmi registers. Byte width accesses (writeb, readb) generate an imprecise external abort. Signed-off-by: Andy Yan --- drivers/gpu/drm/bridge/dw_hdmi.c | 57 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 55 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/bridge/dw_hdmi.c b/drivers/gpu/drm/bridge/dw_hdmi.c index e9e73a7..52158ee 100644 --- a/drivers/gpu/drm/bridge/dw_hdmi.c +++ b/drivers/gpu/drm/bridge/dw_hdmi.c @@ -126,16 +126,39 @@ struct dw_hdmi { unsigned int sample_rate; int ratio; + void (*write)(u8 val, void __iomem *addr); + u8 (*read)(void __iomem *addr); + int reg_shift; }; +static void dw_hdmi_writel(u8 val, void __iomem *addr) +{ + writel(val, addr); +} + +static u8 dw_hdmi_readl(void __iomem *addr) +{ + return readl(addr); +} + +static void dw_hdmi_writeb(u8 val, void __iomem *addr) +{ + writeb(val, addr); +} + +static u8 dw_hdmi_readb(void __iomem *addr) +{ + return readb(addr); +} + static inline void hdmi_writeb(struct dw_hdmi *hdmi, u8 val, int offset) { - writeb(val, hdmi->regs + offset); + hdmi->write(val, hdmi->regs + (offset << hdmi->reg_shift)); } static inline u8 hdmi_readb(struct dw_hdmi *hdmi, int offset) { - return readb(hdmi->regs + offset); + return hdmi->read(hdmi->regs + (offset << hdmi->reg_shift)); } static void hdmi_modb(struct dw_hdmi *hdmi, u8 data, u8 mask, unsigned reg) @@ -1499,6 +1522,36 @@ static int dw_hdmi_bind(struct device *dev, struct device *master, void *data) struct device_node *ddc_node; struct resource *iores; int ret, irq; + u32 val = 1; + + hdmi = devm_kzalloc(&pdev->dev, sizeof(*hdmi), GFP_KERNEL); + if (!hdmi) + return -ENOMEM; + + hdmi->plat_data = plat_data; + hdmi->dev = &pdev->dev; + hdmi->dev_type = plat_data->dev_type; + hdmi->sample_rate = 48000; + hdmi->ratio = 100; + hdmi->encoder = encoder; + + of_property_read_u32(np, "reg-io-width", &val); + + switch (val) { + case 4: + hdmi->write = dw_hdmi_writel; + hdmi->read = dw_hdmi_readl; + hdmi->reg_shift = 2; + break; + case 1: + hdmi->write = dw_hdmi_writeb; + hdmi->read = dw_hdmi_readb; + hdmi->reg_shift = 0; + break; + default: + dev_err(dev, "reg-io-width must be 1 or 4\n"); + return -EINVAL; + } ddc_node = of_parse_phandle(np, "ddc-i2c-bus", 0); if (ddc_node) { -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/