From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934049AbbCPRLw (ORCPT ); Mon, 16 Mar 2015 13:11:52 -0400 Received: from mailgw1.uni-kl.de ([131.246.120.220]:48186 "EHLO mailgw1.uni-kl.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933110AbbCPRI5 (ORCPT ); Mon, 16 Mar 2015 13:08:57 -0400 From: =?UTF-8?q?Thomas=20Niederpr=C3=BCm?= To: plagnioj@jcrosoft.com, tomi.valkeinen@ti.com, maxime.ripard@free-electrons.com, kernel@pengutronix.de, shawn.guo@linaro.org, robh+dt@kernel.org Cc: linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, =?UTF-8?q?Thomas=20Niederpr=C3=BCm?= Subject: [PATCHv4 04/10] fbdev: ssd1307fb: Unify init code and obtain hw specific bits from DT Date: Mon, 16 Mar 2015 18:11:52 +0100 Message-Id: <1426525918-12745-5-git-send-email-niederp@physik.uni-kl.de> X-Mailer: git-send-email 2.3.0 In-Reply-To: <1426525918-12745-1-git-send-email-niederp@physik.uni-kl.de> References: <1423261694-5939-1-git-send-email-niederp@physik.uni-kl.de> <1426525918-12745-1-git-send-email-niederp@physik.uni-kl.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The 130X controllers are very similar from the configuration point of view. The configuration registers for the SSD1305/6/7 are bit identical (except the the VHCOM register and the the default values for clock setup register). This patch unifies the init code of the controller and adds hardware specific properties to DT that are needed to correctly initialize the device. The SSD130X can be wired to the OLED panel in various ways. Even for the same controller this wiring can differ from one display module to another and can not be probed by software. The added DT properties reflect these hardware decisions of the display module manufacturer. The 'com-sequential', 'com-lrremap' and 'com-invdir' values define different possibilities for the COM signals pin configuration and readout direction of the video memory. The 'segment-no-remap' allows the inversion of the memory-to-pin mapping ultimately inverting the order of the controllers output pins. The 'prechargepX' values need to be adapted according the capacitance of the OLEDs pixel cells. So far these hardware specific bits are hard coded in the init code, making the driver usable only for one certain wiring of the controller. This patch makes the driver usable with all possible hardware setups, given a valid hw description in DT. If these values are not set in DT the default values, as they are set in the ssd1307 init code right now, are used. This implies that without the corresponding DT property "segment-no-remap" the segment remap of the ssd130X controller gets activated. Even though this is not the default behaviour according to the datasheet it maintains backward compatibility with older DTBs. Note that the SSD1306 does not seem to be using the configuration written to the registers at all. Therefore this patch does not try to maintain these values without changes in DT. For reference an example is added to the DT bindings documentation that reproduces the configuration that is set in the current init code. Signed-off-by: Thomas Niederprüm --- .../devicetree/bindings/video/ssd1307fb.txt | 21 +++ drivers/video/fbdev/ssd1307fb.c | 195 ++++++++++++--------- 2 files changed, 137 insertions(+), 79 deletions(-) diff --git a/Documentation/devicetree/bindings/video/ssd1307fb.txt b/Documentation/devicetree/bindings/video/ssd1307fb.txt index 7a12542..be27562 100644 --- a/Documentation/devicetree/bindings/video/ssd1307fb.txt +++ b/Documentation/devicetree/bindings/video/ssd1307fb.txt @@ -15,6 +15,16 @@ Required properties: Optional properties: - reset-active-low: Is the reset gpio is active on physical low? + - solomon,segment-no-remap: Display needs normal (non-inverted) data column + to segment mapping + - solomon,com-sequential: Display uses sequential COM pin configuration + - solomon,com-lrremap: Display uses left-right COM pin remap + - solomon,com-invdir: Display uses inverted COM pin scan direction + - solomon,com-offset: Offset of the first COM pin wired to the panel + - solomon,prechargep1: Length of deselect period (phase 1) in clock cycles. + - solomon,prechargep2: Length of precharge period (phase 2) in clock cycles. + This needs to be the higher, the higher the capacitance + of the OLED's pixels is [0]: Documentation/devicetree/bindings/pwm/pwm.txt @@ -26,3 +36,14 @@ ssd1307: oled@3c { reset-gpios = <&gpio2 7>; reset-active-low; }; + +ssd1306: oled@3c { + compatible = "solomon,ssd1306fb-i2c"; + reg = <0x3c>; + pwms = <&pwm 4 3000>; + reset-gpios = <&gpio2 7>; + reset-active-low; + solomon,com-lrremap; + solomon,com-invdir; + solomon,com-offset = <32>; +}; diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c index 8d34c56..9a66118 100644 --- a/drivers/video/fbdev/ssd1307fb.c +++ b/drivers/video/fbdev/ssd1307fb.c @@ -16,6 +16,9 @@ #include #include +#define DEVID_SSD1306 6 +#define DEVID_SSD1307 7 + #define SSD1307FB_DATA 0x40 #define SSD1307FB_COMMAND 0x80 @@ -38,22 +41,38 @@ #define SSD1307FB_SET_COM_PINS_CONFIG 0xda #define SSD1307FB_SET_VCOMH 0xdb +static u_int contrast = 128; +module_param(contrast, uint, S_IRUGO); + struct ssd1307fb_par; -struct ssd1307fb_ops { - int (*init)(struct ssd1307fb_par *); - int (*remove)(struct ssd1307fb_par *); +struct ssd1307fb_deviceinfo { + int device_id; + u32 default_vcomh; + u32 default_dclk_div; + u32 default_dclk_frq; }; struct ssd1307fb_par { + u32 com_invdir; + u32 com_lrremap; + u32 com_offset; + u32 com_seq; + u32 contrast; + u32 dclk_div; + u32 dclk_frq; + struct ssd1307fb_deviceinfo *device_info; struct i2c_client *client; u32 height; struct fb_info *info; - struct ssd1307fb_ops *ops; u32 page_offset; + u32 prechargep1; + u32 prechargep2; struct pwm_device *pwm; u32 pwm_period; int reset; + u32 seg_remap; + u32 vcomh; u32 width; }; @@ -254,69 +273,46 @@ static struct fb_deferred_io ssd1307fb_defio = { .deferred_io = ssd1307fb_deferred_io, }; -static int ssd1307fb_ssd1307_init(struct ssd1307fb_par *par) +static int ssd1307fb_init(struct ssd1307fb_par *par) { int ret; + u32 precharge, dclk, com_invdir, compins; - par->pwm = pwm_get(&par->client->dev, NULL); - if (IS_ERR(par->pwm)) { - dev_err(&par->client->dev, "Could not get PWM from device tree!\n"); - return PTR_ERR(par->pwm); - } - - par->pwm_period = pwm_get_period(par->pwm); - /* Enable the PWM */ - pwm_config(par->pwm, par->pwm_period / 2, par->pwm_period); - pwm_enable(par->pwm); - - dev_dbg(&par->client->dev, "Using PWM%d with a %dns period.\n", - par->pwm->pwm, par->pwm_period); - - /* Map column 127 of the OLED to segment 0 */ - ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SEG_REMAP_ON); - if (ret < 0) - return ret; - - /* Turn on the display */ - ret = ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON); - if (ret < 0) - return ret; - - return 0; -} - -static int ssd1307fb_ssd1307_remove(struct ssd1307fb_par *par) -{ - pwm_disable(par->pwm); - pwm_put(par->pwm); - return 0; -} + if (par->device_info->device_id == DEVID_SSD1307) { + par->pwm = pwm_get(&par->client->dev, NULL); + if (IS_ERR(par->pwm)) { + dev_err(&par->client->dev, "Could not get PWM from device tree!\n"); + return PTR_ERR(par->pwm); + } -static struct ssd1307fb_ops ssd1307fb_ssd1307_ops = { - .init = ssd1307fb_ssd1307_init, - .remove = ssd1307fb_ssd1307_remove, -}; + par->pwm_period = pwm_get_period(par->pwm); + /* Enable the PWM */ + pwm_config(par->pwm, par->pwm_period / 2, par->pwm_period); + pwm_enable(par->pwm); -static int ssd1307fb_ssd1306_init(struct ssd1307fb_par *par) -{ - int ret; + dev_dbg(&par->client->dev, "Using PWM%d with a %dns period.\n", + par->pwm->pwm, par->pwm_period); + }; /* Set initial contrast */ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST); if (ret < 0) return ret; - ret = ssd1307fb_write_cmd(par->client, 0x7f); - if (ret < 0) - return ret; - - /* Set COM direction */ - ret = ssd1307fb_write_cmd(par->client, 0xc8); + ret = ssd1307fb_write_cmd(par->client, par->contrast); if (ret < 0) return ret; /* Set segment re-map */ - ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SEG_REMAP_ON); + if (par->seg_remap) { + ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SEG_REMAP_ON); + if (ret < 0) + return ret; + }; + + /* Set COM direction */ + com_invdir = 0xc0 | (par->com_invdir & 0xf) << 3; + ret = ssd1307fb_write_cmd(par->client, com_invdir); if (ret < 0) return ret; @@ -334,34 +330,38 @@ static int ssd1307fb_ssd1306_init(struct ssd1307fb_par *par) if (ret < 0) return ret; - ret = ssd1307fb_write_cmd(par->client, 0x20); + ret = ssd1307fb_write_cmd(par->client, par->com_offset); if (ret < 0) return ret; /* Set clock frequency */ + dclk = (par->dclk_div & 0xf) | (par->dclk_frq & 0xf) << 4; ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_CLOCK_FREQ); if (ret < 0) return ret; - ret = ssd1307fb_write_cmd(par->client, 0xf0); + ret = ssd1307fb_write_cmd(par->client, dclk); if (ret < 0) return ret; /* Set precharge period in number of ticks from the internal clock */ + precharge = (par->prechargep1 & 0xf) | (par->prechargep2 & 0xf) << 4; ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PRECHARGE_PERIOD); if (ret < 0) return ret; - ret = ssd1307fb_write_cmd(par->client, 0x22); + ret = ssd1307fb_write_cmd(par->client, precharge); if (ret < 0) return ret; /* Set COM pins configuration */ + compins = 0x02 | (!par->com_seq & 0x1) << 4 + | (par->com_lrremap & 0x1) << 5; ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COM_PINS_CONFIG); if (ret < 0) return ret; - ret = ssd1307fb_write_cmd(par->client, 0x22); + ret = ssd1307fb_write_cmd(par->client, compins); if (ret < 0) return ret; @@ -370,18 +370,20 @@ static int ssd1307fb_ssd1306_init(struct ssd1307fb_par *par) if (ret < 0) return ret; - ret = ssd1307fb_write_cmd(par->client, 0x49); + ret = ssd1307fb_write_cmd(par->client, par->vcomh); if (ret < 0) return ret; - /* Turn on the DC-DC Charge Pump */ - ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CHARGE_PUMP); - if (ret < 0) - return ret; + if (par->device_info->device_id == DEVID_SSD1306) { + /* Turn on the DC-DC Charge Pump */ + ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CHARGE_PUMP); + if (ret < 0) + return ret; - ret = ssd1307fb_write_cmd(par->client, 0x14); - if (ret < 0) - return ret; + ret = ssd1307fb_write_cmd(par->client, 0x14); + if (ret < 0) + return ret; + }; /* Switch to horizontal addressing mode */ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_ADDRESS_MODE); @@ -393,6 +395,7 @@ static int ssd1307fb_ssd1306_init(struct ssd1307fb_par *par) if (ret < 0) return ret; + /* Set column range */ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COL_RANGE); if (ret < 0) return ret; @@ -405,6 +408,7 @@ static int ssd1307fb_ssd1306_init(struct ssd1307fb_par *par) if (ret < 0) return ret; + /* Set page range */ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PAGE_RANGE); if (ret < 0) return ret; @@ -426,18 +430,28 @@ static int ssd1307fb_ssd1306_init(struct ssd1307fb_par *par) return 0; } -static struct ssd1307fb_ops ssd1307fb_ssd1306_ops = { - .init = ssd1307fb_ssd1306_init, +static struct ssd1307fb_deviceinfo ssd1307fb_ssd1306_deviceinfo = { + .device_id = DEVID_SSD1306, + .default_vcomh = 0x20, + .default_dclk_div = 0, + .default_dclk_frq = 8, +}; + +static struct ssd1307fb_deviceinfo ssd1307fb_ssd1307_deviceinfo = { + .device_id = DEVID_SSD1307, + .default_vcomh = 0x20, + .default_dclk_div = 1, + .default_dclk_frq = 12, }; static const struct of_device_id ssd1307fb_of_match[] = { { .compatible = "solomon,ssd1306fb-i2c", - .data = (void *)&ssd1307fb_ssd1306_ops, + .data = (void *)&ssd1307fb_ssd1306_deviceinfo, }, { .compatible = "solomon,ssd1307fb-i2c", - .data = (void *)&ssd1307fb_ssd1307_ops, + .data = (void *)&ssd1307fb_ssd1307_deviceinfo, }, {}, }; @@ -468,8 +482,8 @@ static int ssd1307fb_probe(struct i2c_client *client, par->info = info; par->client = client; - par->ops = (struct ssd1307fb_ops *)of_match_device(ssd1307fb_of_match, - &client->dev)->data; + par->device_info = (struct ssd1307fb_deviceinfo *)of_match_device( + ssd1307fb_of_match, &client->dev)->data; par->reset = of_get_named_gpio(client->dev.of_node, "reset-gpios", 0); @@ -487,6 +501,27 @@ static int ssd1307fb_probe(struct i2c_client *client, if (of_property_read_u32(node, "solomon,page-offset", &par->page_offset)) par->page_offset = 1; + if (of_property_read_u32(node, "solomon,com-offset", &par->com_offset)) + par->com_offset = 0; + + if (of_property_read_u32(node, "solomon,prechargep1", &par->prechargep1)) + par->prechargep1 = 2; + + if (of_property_read_u32(node, "solomon,prechargep2", &par->prechargep2)) + par->prechargep2 = 0; + + par->seg_remap = !of_property_read_bool(node, "solomon,segment-no-remap"); + par->com_seq = of_property_read_bool(node, "solomon,com-sequential"); + par->com_lrremap = of_property_read_bool(node, "solomon,com-lrremap"); + par->com_invdir = of_property_read_bool(node, "solomon,com-invdir"); + + par->contrast = contrast; + par->vcomh = par->device_info->default_vcomh; + + /* Setup display timing */ + par->dclk_div = par->device_info->default_dclk_div; + par->dclk_frq = par->device_info->default_dclk_frq; + vmem_size = par->width * par->height / 8; vmem = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, @@ -539,11 +574,9 @@ static int ssd1307fb_probe(struct i2c_client *client, gpio_set_value(par->reset, 1); udelay(4); - if (par->ops->init) { - ret = par->ops->init(par); - if (ret) - goto reset_oled_error; - } + ret = ssd1307fb_init(par); + if (ret) + goto reset_oled_error; ret = register_framebuffer(info); if (ret) { @@ -556,8 +589,10 @@ static int ssd1307fb_probe(struct i2c_client *client, return 0; panel_init_error: - if (par->ops->remove) - par->ops->remove(par); + if (par->device_info->device_id == DEVID_SSD1307) { + pwm_disable(par->pwm); + pwm_put(par->pwm); + }; reset_oled_error: fb_deferred_io_cleanup(info); fb_alloc_error: @@ -571,8 +606,10 @@ static int ssd1307fb_remove(struct i2c_client *client) struct ssd1307fb_par *par = info->par; unregister_framebuffer(info); - if (par->ops->remove) - par->ops->remove(par); + if (par->device_info->device_id == DEVID_SSD1307) { + pwm_disable(par->pwm); + pwm_put(par->pwm); + }; fb_deferred_io_cleanup(info); __free_pages(__va(info->fix.smem_start), get_order(info->fix.smem_len)); framebuffer_release(info); -- 2.3.0