[v6] drm: bridge/dw_hdmi: add dw hdmi i2c bus adapter support

Message ID	1472017597-11221-1-git-send-email-vladimir_zapolskiy@mentor.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <dri-devel-bounces@lists.freedesktop.org> From: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> To: David Airlie <airlied@linux.ie>, Daniel Vetter <daniel.vetter@ffwll.ch>, Russell King <rmk+kernel@arm.linux.org.uk> Subject: [PATCH v6] drm: bridge/dw_hdmi: add dw hdmi i2c bus adapter support Date: Wed, 24 Aug 2016 08:46:37 +0300 Message-ID: <1472017597-11221-1-git-send-email-vladimir_zapolskiy@mentor.com> MIME-Version: 1.0 Cc: devicetree@vger.kernel.org, dri-devel@lists.freedesktop.org Precedence: list Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" <dri-devel-bounces@lists.freedesktop.org>

diff --git a/Documentation/devicetree/bindings/display/bridge/dw_hdmi.txt b/Documentation/devicetree/bindings/display/bridge/dw_hdmi.txt index dc1452f0d5d8..5e9a84d6e5f1 100644 --- a/Documentation/devicetree/bindings/display/bridge/dw_hdmi.txt +++ b/Documentation/devicetree/bindings/display/bridge/dw_hdmi.txt @@ -19,7 +19,9 @@ Required properties: Optional properties - reg-io-width: the width of the reg:1,4, default set to 1 if not present -- ddc-i2c-bus: phandle of an I2C controller used for DDC EDID probing +- ddc-i2c-bus: phandle of an I2C controller used for DDC EDID probing, + if the property is omitted, a functionally reduced I2C bus + controller on DW HDMI is probed - clocks, clock-names: phandle to the HDMI CEC clock, name should be "cec" Example: diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c b/drivers/gpu/drm/bridge/dw-hdmi.c index ce3527cd0d25..cdf0a3a2e6f8 100644 --- a/drivers/gpu/drm/bridge/dw-hdmi.c +++ b/drivers/gpu/drm/bridge/dw-hdmi.c @@ -1,14 +1,15 @@ /* + * DesignWare High-Definition Multimedia Interface (HDMI) driver + * + * Copyright (C) 2013-2015 Mentor Graphics Inc. * Copyright (C) 2011-2013 Freescale Semiconductor, Inc. + * Copyright (C) 2010, Guennadi Liakhovetski <g.liakhovetski@gmx.de> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * - * Designware High-Definition Multimedia Interface (HDMI) driver - * - * Copyright (C) 2010, Guennadi Liakhovetski <g.liakhovetski@gmx.de> */ #include <linux/module.h> #include <linux/irq.h> @@ -101,6 +102,17 @@ struct hdmi_data_info { struct hdmi_vmode video_mode; }; +struct dw_hdmi_i2c { + struct i2c_adapter adap; + + struct mutex lock; /* used to serialize data transfers */ + struct completion cmp; + u8 stat; + + u8 slave_reg; + bool is_regaddr; +}; + struct dw_hdmi { struct drm_connector connector; struct drm_encoder *encoder; @@ -111,6 +123,7 @@ struct dw_hdmi { struct device *dev; struct clk *isfr_clk; struct clk *iahb_clk; + struct dw_hdmi_i2c *i2c; struct hdmi_data_info hdmi_data; const struct dw_hdmi_plat_data *plat_data; @@ -198,6 +211,201 @@ static void hdmi_mask_writeb(struct dw_hdmi *hdmi, u8 data, unsigned int reg, hdmi_modb(hdmi, data << shift, mask, reg); } +static void dw_hdmi_i2c_init(struct dw_hdmi *hdmi) +{ + /* Software reset */ + hdmi_writeb(hdmi, 0x00, HDMI_I2CM_SOFTRSTZ); + + /* Set Standard Mode speed (determined to be 100KHz on iMX6) */ + hdmi_writeb(hdmi, 0x00, HDMI_I2CM_DIV); + + /* Set done, not acknowledged and arbitration interrupt polarities */ + hdmi_writeb(hdmi, HDMI_I2CM_INT_DONE_POL, HDMI_I2CM_INT); + hdmi_writeb(hdmi, HDMI_I2CM_CTLINT_NAC_POL | HDMI_I2CM_CTLINT_ARB_POL, + HDMI_I2CM_CTLINT); + + /* Clear DONE and ERROR interrupts */ + hdmi_writeb(hdmi, HDMI_IH_I2CM_STAT0_ERROR | HDMI_IH_I2CM_STAT0_DONE, + HDMI_IH_I2CM_STAT0); + + /* Mute DONE and ERROR interrupts */ + hdmi_writeb(hdmi, HDMI_IH_I2CM_STAT0_ERROR | HDMI_IH_I2CM_STAT0_DONE, + HDMI_IH_MUTE_I2CM_STAT0); +} + +static int dw_hdmi_i2c_read(struct dw_hdmi *hdmi, + unsigned char *buf, unsigned int length) +{ + struct dw_hdmi_i2c *i2c = hdmi->i2c; + int stat; + + if (!i2c->is_regaddr) { + dev_dbg(hdmi->dev, "set read register address to 0\n"); + i2c->slave_reg = 0x00; + i2c->is_regaddr = true; + } + + while (length--) { + reinit_completion(&i2c->cmp); + + hdmi_writeb(hdmi, i2c->slave_reg++, HDMI_I2CM_ADDRESS); + hdmi_writeb(hdmi, HDMI_I2CM_OPERATION_READ, + HDMI_I2CM_OPERATION); + + stat = wait_for_completion_timeout(&i2c->cmp, HZ / 10); + if (!stat) + return -EAGAIN; + + /* Check for error condition on the bus */ + if (i2c->stat & HDMI_IH_I2CM_STAT0_ERROR) + return -EIO; + + *buf++ = hdmi_readb(hdmi, HDMI_I2CM_DATAI); + } + + return 0; +} + +static int dw_hdmi_i2c_write(struct dw_hdmi *hdmi, + unsigned char *buf, unsigned int length) +{ + struct dw_hdmi_i2c *i2c = hdmi->i2c; + int stat; + + if (!i2c->is_regaddr) { + /* Use the first write byte as register address */ + i2c->slave_reg = buf[0]; + length--; + buf++; + i2c->is_regaddr = true; + } + + while (length--) { + reinit_completion(&i2c->cmp); + + hdmi_writeb(hdmi, *buf++, HDMI_I2CM_DATAO); + hdmi_writeb(hdmi, i2c->slave_reg++, HDMI_I2CM_ADDRESS); + hdmi_writeb(hdmi, HDMI_I2CM_OPERATION_WRITE, + HDMI_I2CM_OPERATION); + + stat = wait_for_completion_timeout(&i2c->cmp, HZ / 10); + if (!stat) + return -EAGAIN; + + /* Check for error condition on the bus */ + if (i2c->stat & HDMI_IH_I2CM_STAT0_ERROR) + return -EIO; + } + + return 0; +} + +static int dw_hdmi_i2c_xfer(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + struct dw_hdmi *hdmi = i2c_get_adapdata(adap); + struct dw_hdmi_i2c *i2c = hdmi->i2c; + u8 addr = msgs[0].addr; + int i, ret = 0; + + dev_dbg(hdmi->dev, "xfer: num: %d, addr: %#x\n", num, addr); + + for (i = 0; i < num; i++) { + if (msgs[i].addr != addr) { + dev_warn(hdmi->dev, + "unsupported transfer, changed slave address\n"); + return -EOPNOTSUPP; + } + + if (msgs[i].len == 0) { + dev_dbg(hdmi->dev, + "unsupported transfer %d/%d, no data\n", + i + 1, num); + return -EOPNOTSUPP; + } + } + + mutex_lock(&i2c->lock); + + /* Unmute DONE and ERROR interrupts */ + hdmi_writeb(hdmi, 0x00, HDMI_IH_MUTE_I2CM_STAT0); + + /* Set slave device address taken from the first I2C message */ + hdmi_writeb(hdmi, addr, HDMI_I2CM_SLAVE); + + /* Set slave device register address on transfer */ + i2c->is_regaddr = false; + + for (i = 0; i < num; i++) { + dev_dbg(hdmi->dev, "xfer: num: %d/%d, len: %d, flags: %#x\n", + i + 1, num, msgs[i].len, msgs[i].flags); + + if (msgs[i].flags & I2C_M_RD) + ret = dw_hdmi_i2c_read(hdmi, msgs[i].buf, msgs[i].len); + else + ret = dw_hdmi_i2c_write(hdmi, msgs[i].buf, msgs[i].len); + + if (ret < 0) + break; + } + + if (!ret) + ret = num; + + /* Mute DONE and ERROR interrupts */ + hdmi_writeb(hdmi, HDMI_IH_I2CM_STAT0_ERROR | HDMI_IH_I2CM_STAT0_DONE, + HDMI_IH_MUTE_I2CM_STAT0); + + mutex_unlock(&i2c->lock); + + return ret; +} + +static u32 dw_hdmi_i2c_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm dw_hdmi_algorithm = { + .master_xfer = dw_hdmi_i2c_xfer, + .functionality = dw_hdmi_i2c_func, +}; + +static struct i2c_adapter *dw_hdmi_i2c_adapter(struct dw_hdmi *hdmi) +{ + struct i2c_adapter *adap; + struct dw_hdmi_i2c *i2c; + int ret; + + i2c = devm_kzalloc(hdmi->dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return ERR_PTR(-ENOMEM); + + mutex_init(&i2c->lock); + init_completion(&i2c->cmp); + + adap = &i2c->adap; + adap->class = I2C_CLASS_DDC; + adap->owner = THIS_MODULE; + adap->dev.parent = hdmi->dev; + adap->algo = &dw_hdmi_algorithm; + strlcpy(adap->name, "DesignWare HDMI", sizeof(adap->name)); + i2c_set_adapdata(adap, hdmi); + + ret = i2c_add_adapter(adap); + if (ret) { + dev_warn(hdmi->dev, "cannot add %s I2C adapter\n", adap->name); + devm_kfree(hdmi->dev, i2c); + return ERR_PTR(ret); + } + + hdmi->i2c = i2c; + + dev_info(hdmi->dev, "registered %s I2C bus driver\n", adap->name); + + return adap; +} + static void hdmi_set_cts_n(struct dw_hdmi *hdmi, unsigned int cts, unsigned int n) { @@ -1517,16 +1725,40 @@ static const struct drm_bridge_funcs dw_hdmi_bridge_funcs = { .mode_set = dw_hdmi_bridge_mode_set, }; +static irqreturn_t dw_hdmi_i2c_irq(struct dw_hdmi *hdmi) +{ + struct dw_hdmi_i2c *i2c = hdmi->i2c; + unsigned int stat; + + stat = hdmi_readb(hdmi, HDMI_IH_I2CM_STAT0); + if (!stat) + return IRQ_NONE; + + hdmi_writeb(hdmi, stat, HDMI_IH_I2CM_STAT0); + + i2c->stat = stat; + + complete(&i2c->cmp); + + return IRQ_HANDLED; +} + static irqreturn_t dw_hdmi_hardirq(int irq, void *dev_id) { struct dw_hdmi *hdmi = dev_id; u8 intr_stat; + irqreturn_t ret = IRQ_NONE; + + if (hdmi->i2c) + ret = dw_hdmi_i2c_irq(hdmi); intr_stat = hdmi_readb(hdmi, HDMI_IH_PHY_STAT0); - if (intr_stat) + if (intr_stat) { hdmi_writeb(hdmi, ~0, HDMI_IH_MUTE_PHY_STAT0); + return IRQ_WAKE_THREAD; + } - return intr_stat ? IRQ_WAKE_THREAD : IRQ_NONE; + return ret; } static irqreturn_t dw_hdmi_irq(int irq, void *dev_id) @@ -1751,6 +1983,13 @@ int dw_hdmi_bind(struct device *dev, struct device *master, */ hdmi_init_clk_regenerator(hdmi); + /* If DDC bus is not specified, try to register HDMI I2C bus */ + if (!hdmi->ddc) { + hdmi->ddc = dw_hdmi_i2c_adapter(hdmi); + if (IS_ERR(hdmi->ddc)) + hdmi->ddc = NULL; + } + /* * Configure registers related to HDMI interrupt * generation before registering IRQ. @@ -1791,11 +2030,20 @@ int dw_hdmi_bind(struct device *dev, struct device *master, hdmi->audio = platform_device_register_full(&pdevinfo); } + /* Reset HDMI DDC I2C master controller and mute I2CM interrupts */ + if (hdmi->i2c) + dw_hdmi_i2c_init(hdmi); + dev_set_drvdata(dev, hdmi); return 0; err_iahb: + if (hdmi->i2c) { + i2c_del_adapter(&hdmi->i2c->adap); + hdmi->ddc = NULL; + } + clk_disable_unprepare(hdmi->iahb_clk); err_isfr: clk_disable_unprepare(hdmi->isfr_clk); @@ -1821,13 +2069,18 @@ void dw_hdmi_unbind(struct device *dev, struct device *master, void *data) clk_disable_unprepare(hdmi->iahb_clk); clk_disable_unprepare(hdmi->isfr_clk); - i2c_put_adapter(hdmi->ddc); + + if (hdmi->i2c) + i2c_del_adapter(&hdmi->i2c->adap); + else + i2c_put_adapter(hdmi->ddc); } EXPORT_SYMBOL_GPL(dw_hdmi_unbind); MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>"); MODULE_AUTHOR("Andy Yan <andy.yan@rock-chips.com>"); MODULE_AUTHOR("Yakir Yang <ykk@rock-chips.com>"); +MODULE_AUTHOR("Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>"); MODULE_DESCRIPTION("DW HDMI transmitter driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:dw-hdmi"); diff --git a/drivers/gpu/drm/bridge/dw-hdmi.h b/drivers/gpu/drm/bridge/dw-hdmi.h index fc9a560429d6..6aadc840e888 100644 --- a/drivers/gpu/drm/bridge/dw-hdmi.h +++ b/drivers/gpu/drm/bridge/dw-hdmi.h @@ -566,6 +566,10 @@ enum { HDMI_IH_PHY_STAT0_TX_PHY_LOCK = 0x2, HDMI_IH_PHY_STAT0_HPD = 0x1, +/* IH_I2CM_STAT0 and IH_MUTE_I2CM_STAT0 field values */ + HDMI_IH_I2CM_STAT0_DONE = 0x2, + HDMI_IH_I2CM_STAT0_ERROR = 0x1, + /* IH_MUTE_I2CMPHY_STAT0 field values */ HDMI_IH_MUTE_I2CMPHY_STAT0_I2CMPHYDONE = 0x2, HDMI_IH_MUTE_I2CMPHY_STAT0_I2CMPHYERROR = 0x1, @@ -1032,6 +1036,21 @@ enum { HDMI_A_VIDPOLCFG_HSYNCPOL_MASK = 0x2, HDMI_A_VIDPOLCFG_HSYNCPOL_ACTIVE_HIGH = 0x2, HDMI_A_VIDPOLCFG_HSYNCPOL_ACTIVE_LOW = 0x0, + +/* I2CM_OPERATION field values */ + HDMI_I2CM_OPERATION_WRITE = 0x10, + HDMI_I2CM_OPERATION_READ_EXT = 0x2, + HDMI_I2CM_OPERATION_READ = 0x1, + +/* I2CM_INT field values */ + HDMI_I2CM_INT_DONE_POL = 0x8, + HDMI_I2CM_INT_DONE_MASK = 0x4, + +/* I2CM_CTLINT field values */ + HDMI_I2CM_CTLINT_NAC_POL = 0x80, + HDMI_I2CM_CTLINT_NAC_MASK = 0x40, + HDMI_I2CM_CTLINT_ARB_POL = 0x8, + HDMI_I2CM_CTLINT_ARB_MASK = 0x4, }; #endif /* __DW_HDMI_H__ */

[v6] drm: bridge/dw_hdmi: add dw hdmi i2c bus adapter support

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