From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yw0-f195.google.com ([209.85.161.195]:43494 "EHLO mail-yw0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932274AbeCLUtf (ORCPT ); Mon, 12 Mar 2018 16:49:35 -0400 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 4/8] gpio: pcie-idio-24: Implement get_multiple callback Date: Mon, 12 Mar 2018 16:49:28 -0400 Message-Id: <5d46c780a6e3be82e672dbd17ba70d275e35b51b.1520886945.git.vilhelm.gray@gmail.com> In-Reply-To: References: Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org The ACCES I/O PCIe-IDIO-24 series of devices provides 24 optically-isolated digital inputs accessed via three 8-bit ports. Since eight input lines are acquired on a single port input read, the PCIe-IDIO-24 GPIO driver may improve multiple input reads by utilizing a get_multiple callback. This patch implements the idio_24_gpio_get_multiple function which serves as the respective get_multiple callback. Signed-off-by: William Breathitt Gray --- drivers/gpio/gpio-pcie-idio-24.c | 63 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) diff --git a/drivers/gpio/gpio-pcie-idio-24.c b/drivers/gpio/gpio-pcie-idio-24.c index f666e2e69074..6efc85292c49 100644 --- a/drivers/gpio/gpio-pcie-idio-24.c +++ b/drivers/gpio/gpio-pcie-idio-24.c @@ -193,6 +193,68 @@ static int idio_24_gpio_get(struct gpio_chip *chip, unsigned int offset) return !!(ioread8(&idio24gpio->reg->ttl_in0_7) & offset_mask); } +static int idio_24_gpio_get_multiple(struct gpio_chip *chip, + unsigned long *mask, unsigned long *bits) +{ + struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip); + struct idio_24_gpio_reg __iomem *const reg = idio24gpio->reg; + 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; + const unsigned long out_mode_mask = BIT(1); + + /* 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(®->out0_7); + break; + case 1: + port_state = ioread8(®->out8_15); + break; + case 2: + port_state = ioread8(®->out16_23); + break; + case 3: + port_state = ioread8(®->in0_7); + break; + case 4: + port_state = ioread8(®->in8_15); + break; + case 5: + port_state = ioread8(®->in16_23); + break; + case 6: + /* TTL/CMOS Outputs/Inputs */ + if (ioread8(®->ctl) & out_mode_mask) + port_state = ioread8(®->ttl_out0_7); + else + port_state = ioread8(®->ttl_in0_7); + break; + } + + /* store acquired bits */ + bits[BIT_WORD(i)] |= port_state << bit_word_offset; + } + + return 0; +} + static void idio_24_gpio_set(struct gpio_chip *chip, unsigned int offset, int value) { @@ -397,6 +459,7 @@ static int idio_24_probe(struct pci_dev *pdev, const struct pci_device_id *id) idio24gpio->chip.direction_input = idio_24_gpio_direction_input; idio24gpio->chip.direction_output = idio_24_gpio_direction_output; idio24gpio->chip.get = idio_24_gpio_get; + idio24gpio->chip.get_multiple = idio_24_gpio_get_multiple; idio24gpio->chip.set = idio_24_gpio_set; raw_spin_lock_init(&idio24gpio->lock); -- 2.16.2