From patchwork Thu Apr 7 18:39:40 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eddie James X-Patchwork-Id: 558637 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C83ECC433FE for ; Thu, 7 Apr 2022 18:41:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245097AbiDGSnM (ORCPT ); Thu, 7 Apr 2022 14:43:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241691AbiDGSnL (ORCPT ); Thu, 7 Apr 2022 14:43:11 -0400 Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6525127B1C; Thu, 7 Apr 2022 11:41:10 -0700 (PDT) Received: from pps.filterd (m0127361.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 237Hvtrk023024; Thu, 7 Apr 2022 18:39:47 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=X0/w+ht4B+jaN85pRfLQ7j/u2mfPti3ZQH2HIjLHkQw=; b=QWYgqro1tZXEqlOGBm2XGHRDJSa2twhgedYkU1ntNTqhCPs2zvT2TU6YeRQsSXleuJIO xBDsUowduwkHX/KK9FkFUtye3xrLfoh9UN3C+QG0MSLQxwxIQzm78g+vXYl3aajDcNcb eArF6zI72i7+/XQ7UZl7A6jBJ6ijWxOhGmi7hHVYSrIPwxzK1L+VRj7lP7VzaZXtXCH7 DuPSy4pPZWaSbNbQ6VNCUjoxzd7ImiGhzyWY74gn278fcBUAaS6XFpVtXYTG9MqBBtpA KqaI8dlvoABISqpaJ4JfEXZGZszMCzHtbwtfvtgHLMJ5SFoppxDBQ9L0YlBx+mloV06W qg== Received: from ppma02dal.us.ibm.com (a.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.10]) by mx0a-001b2d01.pphosted.com with ESMTP id 3fa4tgh166-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 07 Apr 2022 18:39:47 +0000 Received: from pps.filterd (ppma02dal.us.ibm.com [127.0.0.1]) by ppma02dal.us.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 237INGg3017743; Thu, 7 Apr 2022 18:39:46 GMT Received: from b01cxnp22035.gho.pok.ibm.com (b01cxnp22035.gho.pok.ibm.com [9.57.198.25]) by ppma02dal.us.ibm.com with ESMTP id 3f6e4b2eeb-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 07 Apr 2022 18:39:46 +0000 Received: from b01ledav002.gho.pok.ibm.com (b01ledav002.gho.pok.ibm.com [9.57.199.107]) by b01cxnp22035.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 237IdjwS14221672 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 7 Apr 2022 18:39:45 GMT Received: from b01ledav002.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CBBFE12405C; Thu, 7 Apr 2022 18:39:45 +0000 (GMT) Received: from b01ledav002.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0765F124052; Thu, 7 Apr 2022 18:39:45 +0000 (GMT) Received: from v0005c16.aus.stglabs.ibm.com (unknown [9.211.114.26]) by b01ledav002.gho.pok.ibm.com (Postfix) with ESMTP; Thu, 7 Apr 2022 18:39:44 +0000 (GMT) From: Eddie James To: linux-leds@vger.kernel.org Cc: linux-kernel@vger.kernel.org, pavel@ucw.cz, openbmc@lists.ozlabs.org, joel@jms.id.au, patrick@stwcx.xyz, Eddie James Subject: [PATCH v2 1/2] leds: pca955x: Clean up and optimize Date: Thu, 7 Apr 2022 13:39:40 -0500 Message-Id: <20220407183941.36555-2-eajames@linux.ibm.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20220407183941.36555-1-eajames@linux.ibm.com> References: <20220407183941.36555-1-eajames@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: K6ReIpX5mBIObrUOI8TcR515NuYvLtAf X-Proofpoint-ORIG-GUID: K6ReIpX5mBIObrUOI8TcR515NuYvLtAf X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.425,FMLib:17.11.64.514 definitions=2022-04-07_04,2022-04-07_01,2022-02-23_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 impostorscore=0 spamscore=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 mlxscore=0 lowpriorityscore=0 mlxlogscore=782 clxscore=1011 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2202240000 definitions=main-2204070092 Precedence: bulk List-ID: X-Mailing-List: linux-leds@vger.kernel.org Clean up the I2C access functions to avoid fetching the pca955x driver data again. Optimize the probe to do at most 4 reads and 4 writes of the LED selector regs, rather than 16 of each. Rename some functions and variables to be more consistent and descriptive. Signed-off-by: Eddie James --- drivers/leds/leds-pca955x.c | 148 ++++++++++++++++++++---------------- 1 file changed, 82 insertions(+), 66 deletions(-) diff --git a/drivers/leds/leds-pca955x.c b/drivers/leds/leds-pca955x.c index 81aaf21212d7..dd51f40973d8 100644 --- a/drivers/leds/leds-pca955x.c +++ b/drivers/leds/leds-pca955x.c @@ -140,13 +140,13 @@ struct pca955x_platform_data { }; /* 8 bits per input register */ -static inline int pca95xx_num_input_regs(int bits) +static inline int pca955x_num_input_regs(int bits) { return (bits + 7) / 8; } /* 4 bits per LED selector register */ -static inline int pca95xx_num_led_regs(int bits) +static inline int pca955x_num_led_regs(int bits) { return (bits + 3) / 4; } @@ -161,20 +161,25 @@ static inline u8 pca955x_ledsel(u8 oldval, int led_num, int state) ((state & 0x3) << (led_num << 1)); } +static inline int pca955x_ledstate(u8 ls, int led_num) +{ + return (ls >> (led_num << 1)) & 0x3; +} + /* * Write to frequency prescaler register, used to program the * period of the PWM output. period = (PSCx + 1) / 38 */ -static int pca955x_write_psc(struct i2c_client *client, int n, u8 val) +static int pca955x_write_psc(struct pca955x *pca955x, int n, u8 val) { - struct pca955x *pca955x = i2c_get_clientdata(client); - u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + (2 * n); + u8 cmd = pca955x_num_input_regs(pca955x->chipdef->bits) + (2 * n); int ret; - ret = i2c_smbus_write_byte_data(client, cmd, val); + ret = i2c_smbus_write_byte_data(pca955x->client, cmd, val); if (ret < 0) - dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n", - __func__, n, val, ret); + dev_err(&pca955x->client->dev, + "%s: reg 0x%x, val 0x%x, err %d\n", __func__, n, val, + ret); return ret; } @@ -185,16 +190,16 @@ static int pca955x_write_psc(struct i2c_client *client, int n, u8 val) * * Duty cycle is (256 - PWMx) / 256 */ -static int pca955x_write_pwm(struct i2c_client *client, int n, u8 val) +static int pca955x_write_pwm(struct pca955x *pca955x, int n, u8 val) { - struct pca955x *pca955x = i2c_get_clientdata(client); - u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n); + u8 cmd = pca955x_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n); int ret; - ret = i2c_smbus_write_byte_data(client, cmd, val); + ret = i2c_smbus_write_byte_data(pca955x->client, cmd, val); if (ret < 0) - dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n", - __func__, n, val, ret); + dev_err(&pca955x->client->dev, + "%s: reg 0x%x, val 0x%x, err %d\n", __func__, n, val, + ret); return ret; } @@ -202,16 +207,16 @@ static int pca955x_write_pwm(struct i2c_client *client, int n, u8 val) * Write to LED selector register, which determines the source that * drives the LED output. */ -static int pca955x_write_ls(struct i2c_client *client, int n, u8 val) +static int pca955x_write_ls(struct pca955x *pca955x, int n, u8 val) { - struct pca955x *pca955x = i2c_get_clientdata(client); - u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n; + u8 cmd = pca955x_num_input_regs(pca955x->chipdef->bits) + 4 + n; int ret; - ret = i2c_smbus_write_byte_data(client, cmd, val); + ret = i2c_smbus_write_byte_data(pca955x->client, cmd, val); if (ret < 0) - dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n", - __func__, n, val, ret); + dev_err(&pca955x->client->dev, + "%s: reg 0x%x, val 0x%x, err %d\n", __func__, n, val, + ret); return ret; } @@ -219,15 +224,14 @@ static int pca955x_write_ls(struct i2c_client *client, int n, u8 val) * Read the LED selector register, which determines the source that * drives the LED output. */ -static int pca955x_read_ls(struct i2c_client *client, int n, u8 *val) +static int pca955x_read_ls(struct pca955x *pca955x, int n, u8 *val) { - struct pca955x *pca955x = i2c_get_clientdata(client); - u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n; + u8 cmd = pca955x_num_input_regs(pca955x->chipdef->bits) + 4 + n; int ret; - ret = i2c_smbus_read_byte_data(client, cmd); + ret = i2c_smbus_read_byte_data(pca955x->client, cmd); if (ret < 0) { - dev_err(&client->dev, "%s: reg 0x%x, err %d\n", + dev_err(&pca955x->client->dev, "%s: reg 0x%x, err %d\n", __func__, n, ret); return ret; } @@ -235,15 +239,14 @@ static int pca955x_read_ls(struct i2c_client *client, int n, u8 *val) return 0; } -static int pca955x_read_pwm(struct i2c_client *client, int n, u8 *val) +static int pca955x_read_pwm(struct pca955x *pca955x, int n, u8 *val) { - struct pca955x *pca955x = i2c_get_clientdata(client); - u8 cmd = pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n); + u8 cmd = pca955x_num_input_regs(pca955x->chipdef->bits) + 1 + (2 * n); int ret; - ret = i2c_smbus_read_byte_data(client, cmd); + ret = i2c_smbus_read_byte_data(pca955x->client, cmd); if (ret < 0) { - dev_err(&client->dev, "%s: reg 0x%x, err %d\n", + dev_err(&pca955x->client->dev, "%s: reg 0x%x, err %d\n", __func__, n, ret); return ret; } @@ -260,12 +263,11 @@ static enum led_brightness pca955x_led_get(struct led_classdev *led_cdev) u8 ls, pwm; int ret; - ret = pca955x_read_ls(pca955x->client, pca955x_led->led_num / 4, &ls); + ret = pca955x_read_ls(pca955x, pca955x_led->led_num / 4, &ls); if (ret) return ret; - ls = (ls >> ((pca955x_led->led_num % 4) << 1)) & 0x3; - switch (ls) { + switch (pca955x_ledstate(ls, pca955x_led->led_num % 4)) { case PCA955X_LS_LED_ON: ret = LED_FULL; break; @@ -276,7 +278,7 @@ static enum led_brightness pca955x_led_get(struct led_classdev *led_cdev) ret = LED_HALF; break; case PCA955X_LS_BLINK1: - ret = pca955x_read_pwm(pca955x->client, 1, &pwm); + ret = pca955x_read_pwm(pca955x, 1, &pwm); if (ret) return ret; ret = 255 - pwm; @@ -289,34 +291,30 @@ static enum led_brightness pca955x_led_get(struct led_classdev *led_cdev) static int pca955x_led_set(struct led_classdev *led_cdev, enum led_brightness value) { - struct pca955x_led *pca955x_led; - struct pca955x *pca955x; + struct pca955x_led *pca955x_led = container_of(led_cdev, + struct pca955x_led, + led_cdev); + struct pca955x *pca955x = pca955x_led->pca955x; + int reg = pca955x_led->led_num / 4; + int bit = pca955x_led->led_num % 4; u8 ls; - int chip_ls; /* which LSx to use (0-3 potentially) */ - int ls_led; /* which set of bits within LSx to use (0-3) */ int ret; - pca955x_led = container_of(led_cdev, struct pca955x_led, led_cdev); - pca955x = pca955x_led->pca955x; - - chip_ls = pca955x_led->led_num / 4; - ls_led = pca955x_led->led_num % 4; - mutex_lock(&pca955x->lock); - ret = pca955x_read_ls(pca955x->client, chip_ls, &ls); + ret = pca955x_read_ls(pca955x, reg, &ls); if (ret) goto out; switch (value) { case LED_FULL: - ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_ON); + ls = pca955x_ledsel(ls, bit, PCA955X_LS_LED_ON); break; case LED_OFF: - ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_OFF); + ls = pca955x_ledsel(ls, bit, PCA955X_LS_LED_OFF); break; case LED_HALF: - ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK0); + ls = pca955x_ledsel(ls, bit, PCA955X_LS_BLINK0); break; default: /* @@ -326,14 +324,14 @@ static int pca955x_led_set(struct led_classdev *led_cdev, * OFF, HALF, or FULL. But, this is probably better than * just turning off for all other values. */ - ret = pca955x_write_pwm(pca955x->client, 1, 255 - value); + ret = pca955x_write_pwm(pca955x, 1, 255 - value); if (ret) goto out; - ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK1); + ls = pca955x_ledsel(ls, bit, PCA955X_LS_BLINK1); break; } - ret = pca955x_write_ls(pca955x->client, chip_ls, ls); + ret = pca955x_write_ls(pca955x, reg, ls); out: mutex_unlock(&pca955x->lock); @@ -492,7 +490,9 @@ static int pca955x_probe(struct i2c_client *client) struct led_classdev *led; struct led_init_data init_data; struct i2c_adapter *adapter; - int i, err; + int i, bit, err, nls, reg; + u8 ls1[4]; + u8 ls2[4]; struct pca955x_platform_data *pdata; bool set_default_label = false; bool keep_pwm = false; @@ -563,6 +563,15 @@ static int pca955x_probe(struct i2c_client *client) init_data.devname_mandatory = false; init_data.devicename = "pca955x"; + nls = pca955x_num_led_regs(chip->bits); + for (i = 0; i < nls; ++i) { + err = pca955x_read_ls(pca955x, i, &ls1[i]); + if (err) + return err; + + ls2[i] = ls1[i]; + } + for (i = 0; i < chip->bits; i++) { pca955x_led = &pca955x->leds[i]; pca955x_led->led_num = i; @@ -574,21 +583,20 @@ static int pca955x_probe(struct i2c_client *client) case PCA955X_TYPE_GPIO: break; case PCA955X_TYPE_LED: + bit = i % 4; + reg = i / 4; led = &pca955x_led->led_cdev; led->brightness_set_blocking = pca955x_led_set; led->brightness_get = pca955x_led_get; if (pdata->leds[i].default_state == - LEDS_GPIO_DEFSTATE_OFF) { - err = pca955x_led_set(led, LED_OFF); - if (err) - return err; - } else if (pdata->leds[i].default_state == - LEDS_GPIO_DEFSTATE_ON) { - err = pca955x_led_set(led, LED_FULL); - if (err) - return err; - } + LEDS_GPIO_DEFSTATE_OFF) + ls2[reg] = pca955x_ledsel(ls2[reg], bit, + PCA955X_LS_LED_OFF); + else if (pdata->leds[i].default_state == + LEDS_GPIO_DEFSTATE_ON) + ls2[reg] = pca955x_ledsel(ls2[reg], bit, + PCA955X_LS_LED_ON); init_data.fwnode = pdata->leds[i].fwnode; @@ -633,23 +641,31 @@ static int pca955x_probe(struct i2c_client *client) } } + for (i = 0; i < nls; ++i) { + if (ls1[i] != ls2[i]) { + err = pca955x_write_ls(pca955x, i, ls2[i]); + if (err) + return err; + } + } + /* PWM0 is used for half brightness or 50% duty cycle */ - err = pca955x_write_pwm(client, 0, 255 - LED_HALF); + err = pca955x_write_pwm(pca955x, 0, 255 - LED_HALF); if (err) return err; if (!keep_pwm) { /* PWM1 is used for variable brightness, default to OFF */ - err = pca955x_write_pwm(client, 1, 0); + err = pca955x_write_pwm(pca955x, 1, 0); if (err) return err; } /* Set to fast frequency so we do not see flashing */ - err = pca955x_write_psc(client, 0, 0); + err = pca955x_write_psc(pca955x, 0, 0); if (err) return err; - err = pca955x_write_psc(client, 1, 0); + err = pca955x_write_psc(pca955x, 1, 0); if (err) return err; From patchwork Thu Apr 7 18:39:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eddie James X-Patchwork-Id: 558638 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5FBA8C433EF for ; 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Thu, 7 Apr 2022 18:39:45 +0000 (GMT) From: Eddie James To: linux-leds@vger.kernel.org Cc: linux-kernel@vger.kernel.org, pavel@ucw.cz, openbmc@lists.ozlabs.org, joel@jms.id.au, patrick@stwcx.xyz, Eddie James Subject: [PATCH v2 2/2] leds: pca955x: Add HW blink support Date: Thu, 7 Apr 2022 13:39:41 -0500 Message-Id: <20220407183941.36555-3-eajames@linux.ibm.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20220407183941.36555-1-eajames@linux.ibm.com> References: <20220407183941.36555-1-eajames@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: oIO0d2NM1t2JCyydWFUIgkPkcCOX6hCn X-Proofpoint-GUID: oIO0d2NM1t2JCyydWFUIgkPkcCOX6hCn X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.858,Hydra:6.0.425,FMLib:17.11.64.514 definitions=2022-04-07_04,2022-04-07_01,2022-02-23_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 spamscore=0 lowpriorityscore=0 bulkscore=0 mlxlogscore=999 clxscore=1015 adultscore=0 suspectscore=0 impostorscore=0 priorityscore=1501 malwarescore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2202240000 definitions=main-2204070092 Precedence: bulk List-ID: X-Mailing-List: linux-leds@vger.kernel.org Support blinking using the PCA955x chip. Use PWM0 for blinking instead of LED_HALF brightness. Since there is only one frequency and brightness register for any blinking LED, track the blink state of each LED and only support one HW blinking frequency. If another frequency is requested, fallback to software blinking. Signed-off-by: Eddie James --- drivers/leds/leds-pca955x.c | 224 +++++++++++++++++++++++++++--------- 1 file changed, 170 insertions(+), 54 deletions(-) diff --git a/drivers/leds/leds-pca955x.c b/drivers/leds/leds-pca955x.c index dd51f40973d8..d1bbcbbaab68 100644 --- a/drivers/leds/leds-pca955x.c +++ b/drivers/leds/leds-pca955x.c @@ -62,6 +62,8 @@ #define PCA955X_GPIO_HIGH LED_OFF #define PCA955X_GPIO_LOW LED_FULL +#define PCA955X_BLINK_DEFAULT 1000 + enum pca955x_type { pca9550, pca9551, @@ -74,6 +76,7 @@ struct pca955x_chipdef { int bits; u8 slv_addr; /* 7-bit slave address mask */ int slv_addr_shift; /* Number of bits to ignore */ + int blink_div; /* PSC divider */ }; static struct pca955x_chipdef pca955x_chipdefs[] = { @@ -81,26 +84,31 @@ static struct pca955x_chipdef pca955x_chipdefs[] = { .bits = 2, .slv_addr = /* 110000x */ 0x60, .slv_addr_shift = 1, + .blink_div = 44, }, [pca9551] = { .bits = 8, .slv_addr = /* 1100xxx */ 0x60, .slv_addr_shift = 3, + .blink_div = 38, }, [pca9552] = { .bits = 16, .slv_addr = /* 1100xxx */ 0x60, .slv_addr_shift = 3, + .blink_div = 44, }, [ibm_pca9552] = { .bits = 16, .slv_addr = /* 0110xxx */ 0x30, .slv_addr_shift = 3, + .blink_div = 44, }, [pca9553] = { .bits = 4, .slv_addr = /* 110001x */ 0x62, .slv_addr_shift = 1, + .blink_div = 44, }, }; @@ -119,7 +127,9 @@ struct pca955x { struct pca955x_led *leds; struct pca955x_chipdef *chipdef; struct i2c_client *client; + unsigned long active_blink; unsigned long active_pins; + unsigned long blink_period; #ifdef CONFIG_LEDS_PCA955X_GPIO struct gpio_chip gpio; #endif @@ -168,7 +178,7 @@ static inline int pca955x_ledstate(u8 ls, int led_num) /* * Write to frequency prescaler register, used to program the - * period of the PWM output. period = (PSCx + 1) / 38 + * period of the PWM output. period = (PSCx + 1) / <38 or 44, chip dependent> */ static int pca955x_write_psc(struct pca955x *pca955x, int n, u8 val) { @@ -254,6 +264,21 @@ static int pca955x_read_pwm(struct pca955x *pca955x, int n, u8 *val) return 0; } +static int pca955x_read_psc(struct pca955x *pca955x, int n, u8 *val) +{ + u8 cmd = pca955x_num_input_regs(pca955x->chipdef->bits) + (2 * n); + int ret; + + ret = i2c_smbus_read_byte_data(pca955x->client, cmd); + if (ret < 0) { + dev_err(&pca955x->client->dev, "%s: reg 0x%x, err %d\n", + __func__, n, ret); + return ret; + } + *val = (u8)ret; + return 0; +} + static enum led_brightness pca955x_led_get(struct led_classdev *led_cdev) { struct pca955x_led *pca955x_led = container_of(led_cdev, @@ -275,7 +300,10 @@ static enum led_brightness pca955x_led_get(struct led_classdev *led_cdev) ret = LED_OFF; break; case PCA955X_LS_BLINK0: - ret = LED_HALF; + ret = pca955x_read_pwm(pca955x, 0, &pwm); + if (ret) + return ret; + ret = 256 - pwm; break; case PCA955X_LS_BLINK1: ret = pca955x_read_pwm(pca955x, 1, &pwm); @@ -306,29 +334,36 @@ static int pca955x_led_set(struct led_classdev *led_cdev, if (ret) goto out; - switch (value) { - case LED_FULL: - ls = pca955x_ledsel(ls, bit, PCA955X_LS_LED_ON); - break; - case LED_OFF: - ls = pca955x_ledsel(ls, bit, PCA955X_LS_LED_OFF); - break; - case LED_HALF: - ls = pca955x_ledsel(ls, bit, PCA955X_LS_BLINK0); - break; - default: - /* - * Use PWM1 for all other values. This has the unwanted - * side effect of making all LEDs on the chip share the - * same brightness level if set to a value other than - * OFF, HALF, or FULL. But, this is probably better than - * just turning off for all other values. - */ - ret = pca955x_write_pwm(pca955x, 1, 255 - value); - if (ret) + if (test_bit(pca955x_led->led_num, &pca955x->active_blink)) { + if (value == LED_OFF) { + clear_bit(pca955x_led->led_num, &pca955x->active_blink); + ls = pca955x_ledsel(ls, bit, PCA955X_LS_LED_OFF); + } else { + ret = pca955x_write_pwm(pca955x, 0, 256 - value); goto out; - ls = pca955x_ledsel(ls, bit, PCA955X_LS_BLINK1); - break; + } + } else { + switch (value) { + case LED_FULL: + ls = pca955x_ledsel(ls, bit, PCA955X_LS_LED_ON); + break; + case LED_OFF: + ls = pca955x_ledsel(ls, bit, PCA955X_LS_LED_OFF); + break; + default: + /* + * Use PWM1 for all other values. This has the unwanted + * side effect of making all LEDs on the chip share the + * same brightness level if set to a value other than + * OFF or FULL. But, this is probably better than just + * turning off for all other values. + */ + ret = pca955x_write_pwm(pca955x, 1, 255 - value); + if (ret) + goto out; + ls = pca955x_ledsel(ls, bit, PCA955X_LS_BLINK1); + break; + } } ret = pca955x_write_ls(pca955x, reg, ls); @@ -339,6 +374,96 @@ static int pca955x_led_set(struct led_classdev *led_cdev, return ret; } +static u8 pca955x_period_to_psc(struct pca955x *pca955x, unsigned long p) +{ + p *= (unsigned long)pca955x->chipdef->blink_div; + p /= 1000; + p -= 1; + + return (u8)p; +} + +static unsigned long pca955x_psc_to_period(struct pca955x *pca955x, u8 psc) +{ + unsigned long p = (unsigned long)psc; + + p += 1; + p *= 1000; + p /= (unsigned long)pca955x->chipdef->blink_div; + + return p; +} + +static int pca955x_led_blink(struct led_classdev *led_cdev, + unsigned long *delay_on, unsigned long *delay_off) +{ + struct pca955x_led *pca955x_led = container_of(led_cdev, + struct pca955x_led, + led_cdev); + struct pca955x *pca955x = pca955x_led->pca955x; + int ret; + unsigned long p = *delay_on + *delay_off; + + mutex_lock(&pca955x->lock); + + if (!p) { + p = pca955x->active_blink ? pca955x->blink_period : + PCA955X_BLINK_DEFAULT; + } else { + if (*delay_on != *delay_off) { + ret = -EINVAL; + goto out; + } + + if (p < pca955x_psc_to_period(pca955x, 0) || + p > pca955x_psc_to_period(pca955x, 0xff)) { + ret = -EINVAL; + goto out; + } + } + + if (!pca955x->active_blink || + pca955x->active_blink == BIT(pca955x_led->led_num) || + pca955x->blink_period == p) { + u8 psc = pca955x_period_to_psc(pca955x, p); + + if (!test_and_set_bit(pca955x_led->led_num, + &pca955x->active_blink)) { + u8 ls; + int reg = pca955x_led->led_num / 4; + int bit = pca955x_led->led_num % 4; + + ret = pca955x_read_ls(pca955x, reg, &ls); + if (ret) + goto out; + + ls = pca955x_ledsel(ls, bit, PCA955X_LS_BLINK0); + ret = pca955x_write_ls(pca955x, reg, ls); + if (ret) + goto out; + } + + if (pca955x->blink_period != p) { + pca955x->blink_period = p; + ret = pca955x_write_psc(pca955x, 0, psc); + if (ret) + goto out; + } + + p = pca955x_psc_to_period(pca955x, psc); + p /= 2; + *delay_on = p; + *delay_off = p; + } else { + ret = -EBUSY; + } + +out: + mutex_unlock(&pca955x->lock); + + return ret; +} + #ifdef CONFIG_LEDS_PCA955X_GPIO /* * Read the INPUT register, which contains the state of LEDs. @@ -494,8 +619,9 @@ static int pca955x_probe(struct i2c_client *client) u8 ls1[4]; u8 ls2[4]; struct pca955x_platform_data *pdata; + u8 psc0; + bool keep_psc0 = false; bool set_default_label = false; - bool keep_pwm = false; char default_label[8]; enum pca955x_type chip_type; const void *md = device_get_match_data(&client->dev); @@ -559,6 +685,7 @@ static int pca955x_probe(struct i2c_client *client) mutex_init(&pca955x->lock); pca955x->client = client; pca955x->chipdef = chip; + pca955x->blink_period = PCA955X_BLINK_DEFAULT; init_data.devname_mandatory = false; init_data.devicename = "pca955x"; @@ -588,15 +715,21 @@ static int pca955x_probe(struct i2c_client *client) led = &pca955x_led->led_cdev; led->brightness_set_blocking = pca955x_led_set; led->brightness_get = pca955x_led_get; + led->blink_set = pca955x_led_blink; if (pdata->leds[i].default_state == - LEDS_GPIO_DEFSTATE_OFF) + LEDS_GPIO_DEFSTATE_OFF) { ls2[reg] = pca955x_ledsel(ls2[reg], bit, PCA955X_LS_LED_OFF); - else if (pdata->leds[i].default_state == - LEDS_GPIO_DEFSTATE_ON) + } else if (pdata->leds[i].default_state == + LEDS_GPIO_DEFSTATE_ON) { ls2[reg] = pca955x_ledsel(ls2[reg], bit, PCA955X_LS_LED_ON); + } else if (pca955x_ledstate(ls2[reg], bit) == + PCA955X_LS_BLINK0) { + keep_psc0 = true; + set_bit(i, &pca955x->active_blink); + } init_data.fwnode = pdata->leds[i].fwnode; @@ -624,20 +757,6 @@ static int pca955x_probe(struct i2c_client *client) return err; set_bit(i, &pca955x->active_pins); - - /* - * For default-state == "keep", let the core update the - * brightness from the hardware, then check the - * brightness to see if it's using PWM1. If so, PWM1 - * should not be written below. - */ - if (pdata->leds[i].default_state == - LEDS_GPIO_DEFSTATE_KEEP) { - if (led->brightness != LED_FULL && - led->brightness != LED_OFF && - led->brightness != LED_HALF) - keep_pwm = true; - } } } @@ -649,22 +768,19 @@ static int pca955x_probe(struct i2c_client *client) } } - /* PWM0 is used for half brightness or 50% duty cycle */ - err = pca955x_write_pwm(pca955x, 0, 255 - LED_HALF); - if (err) - return err; - - if (!keep_pwm) { - /* PWM1 is used for variable brightness, default to OFF */ - err = pca955x_write_pwm(pca955x, 1, 0); - if (err) - return err; + if (!keep_psc0) { + psc0 = pca955x_period_to_psc(pca955x, pca955x->blink_period); + err = pca955x_write_psc(pca955x, 0, psc0); + } else { + err = pca955x_read_psc(pca955x, 0, &psc0); } - /* Set to fast frequency so we do not see flashing */ - err = pca955x_write_psc(pca955x, 0, 0); if (err) return err; + + pca955x->blink_period = pca955x_psc_to_period(pca955x, psc0); + + /* Set PWM1 to fast frequency so we do not see flashing */ err = pca955x_write_psc(pca955x, 1, 0); if (err) return err;