From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932489AbeCLUtQ (ORCPT ); Mon, 12 Mar 2018 16:49:16 -0400 Received: from mail-yw0-f196.google.com ([209.85.161.196]:33679 "EHLO mail-yw0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932274AbeCLUtO (ORCPT ); Mon, 12 Mar 2018 16:49:14 -0400 X-Google-Smtp-Source: AG47ELu/N6NpQIyoXb8Vyf2fa4QOJVcP1SvFYUGEzszzoySL0bQRCzC3MTA758QoH/OOBeDYbru8OA== From: William Breathitt Gray To: linus.walleij@linaro.org Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, William Breathitt Gray Subject: [PATCH 3/8] gpio: pci-idio-16: Implement get_multiple callback Date: Mon, 12 Mar 2018 16:49:07 -0400 Message-Id: X-Mailer: git-send-email 2.16.2 In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The ACCES I/O PCI-IDIO-16 series of devices provides 16 optically-isolated digital inputs accessed via two 8-bit ports. Since eight input lines are acquired on a single port input read, the PCI-IDIO-16 GPIO driver may improve multiple input reads by utilizing a get_multiple callback. This patch implements the idio_16_gpio_get_multiple function which serves as the respective get_multiple callback. Signed-off-by: William Breathitt Gray --- drivers/gpio/gpio-pci-idio-16.c | 48 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) diff --git a/drivers/gpio/gpio-pci-idio-16.c b/drivers/gpio/gpio-pci-idio-16.c index 57d1b7fbf07b..8c5ec301c7ff 100644 --- a/drivers/gpio/gpio-pci-idio-16.c +++ b/drivers/gpio/gpio-pci-idio-16.c @@ -103,6 +103,53 @@ static int idio_16_gpio_get(struct gpio_chip *chip, unsigned int offset) return !!(ioread8(&idio16gpio->reg->in8_15) & (mask >> 24)); } +static int idio_16_gpio_get_multiple(struct gpio_chip *chip, + unsigned long *mask, unsigned long *bits) +{ + struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip); + unsigned int i; + const unsigned int gpio_reg_size = 8; + unsigned int bit_word_offset; + unsigned int bits_mask; + const unsigned long reg_mask = GENMASK(gpio_reg_size, 0); + unsigned long port_state; + + /* clear bits array to a clean slate */ + for (i = 0; i < chip->ngpio; i += BITS_PER_LONG) + bits[i / BITS_PER_LONG] = 0; + + /* get bits are evaluated a gpio register size at a time */ + for (i = 0; i < chip->ngpio; i += gpio_reg_size) { + bit_word_offset = i % BITS_PER_LONG; + bits_mask = mask[BIT_WORD(i)] & (reg_mask << bit_word_offset); + if (!bits_mask) { + /* no get bits in this register so skip to next one */ + continue; + } + + /* read bits from current gpio register */ + switch (i / gpio_reg_size) { + case 0: + port_state = ioread8(&idio16gpio->reg->out0_7); + break; + case 1: + port_state = ioread8(&idio16gpio->reg->out8_15); + break; + case 2: + port_state = ioread8(&idio16gpio->reg->in0_7); + break; + case 3: + port_state = ioread8(&idio16gpio->reg->in8_15); + break; + } + + /* store acquired bits */ + bits[BIT_WORD(i)] |= port_state << bit_word_offset; + } + + return 0; +} + static void idio_16_gpio_set(struct gpio_chip *chip, unsigned int offset, int value) { @@ -299,6 +346,7 @@ static int idio_16_probe(struct pci_dev *pdev, const struct pci_device_id *id) idio16gpio->chip.direction_input = idio_16_gpio_direction_input; idio16gpio->chip.direction_output = idio_16_gpio_direction_output; idio16gpio->chip.get = idio_16_gpio_get; + idio16gpio->chip.get_multiple = idio_16_gpio_get_multiple; idio16gpio->chip.set = idio_16_gpio_set; idio16gpio->chip.set_multiple = idio_16_gpio_set_multiple; -- 2.16.2