From patchwork Sat Mar 16 01:03:01 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Justin Swartz X-Patchwork-Id: 780814 Received: from outgoing6.flk.host-h.net (outgoing6.flk.host-h.net [188.40.0.77]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 669EB4C61; Sat, 16 Mar 2024 01:02:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=188.40.0.77 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710550972; cv=none; b=bmK5gsyNpUzNZwZx+ImK7wI+5K1WOWzTIGXnna26J0KMVQu5x0Ltphchy990SIItxprC7wJh3kIAMTa+n+JuBR5+lc+hgYjBKT7yXV4P8cm4lMUevQ6iwXJqm24VYJLdnIaDe0cZirVWDull3vgIl3fjoKKREW+Xeo3LAvVpY8I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710550972; c=relaxed/simple; bh=jvr0PIbn0nyqRCyO7pJ0Hs9rBTEJbPJzgG+VYgmmLjQ=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; 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auth=pass (login) smtp.auth=@risingedge.co.za X-SpamExperts-Outgoing-Class: ham X-SpamExperts-Outgoing-Evidence: SB/global_tokens (0.00517244989743) X-Recommended-Action: accept X-Filter-ID: Pt3MvcO5N4iKaDQ5O6lkdGlMVN6RH8bjRMzItlySaT+zATT0e6URdjZkCJyOHeUGPUtbdvnXkggZ 3YnVId/Y5jcf0yeVQAvfjHznO7+bT5wCPRB8bAzJcv2cv+UqiTTc2+CpNcmBnO4XM3Sck4bwNogU WCl1nkLBzZX0KuJ9bXiS85Z42w/+2OBolTNFbPomXFWCX8oNdggW7HE9XDTdSejrkEpbuUvwMvHx 3T+KSG//gbuP7hnUK8NQdLwsVWKIss2oH4Yjh6Q4paNNh70vrmKlRYN8+ZW0XX0AH/7tz8lOUWMR 3Oz/N19DDfqg//ykQCB4rUl3suKct8rEwEjtlBjGf82vsPPH4Z6bBeyJ2ioKLll7c1zqbZ0Shnfk f76m6WzjgyOQ30CX3jGye0AgO43dPg2t4siixN3H6ipUQpvuAkr0ni3BRcXgf14M3f2CWmuNA8WT ybi1JN85FSnfKaZl5e9CnNR0t//S8nh6vX9JR7tTkgtGxbJXMnaWeORi/IOL8hFK8UwSRsjj826v xIvoo9siXVea4yN8+JzC4p2qtoJeAaAIM5zNlwLSz7WsotxMDYRAzuCR0I/uZN17IfdXFZsEUcDk 8TfE1VxuxGc2M4JzCc//R6Wyn0xEa4/gbKRUuwP9TxU53J++//mag2wVXO50BuTihrUiUr+Ne0YD 3ddZG295JphtZpms9X0aBNANCxNWMmHXUTEMGGbKThOghFKJuzFdJ78lk25pCKnYrhUnk1aI/tYo PYfrgLItviC2z3vIzjh1mXBwO7cA3KxDuzsITj9XSEsqBTpMNClkAdhK23InA2zzja5I1riDVsRE /qfh3BpRIL035Lwa3AR5iWi4B3c2TvD1mYFCey4YQsgkfE0ewNgNUY5lZOQ5d86hkdfWpdNtlHKD /N5YI0ii+HGJbtyrZfX5fEH4LjZJ4azDVvtI4xLpBrhpV1Z2g0cC96lvLg9F6alXVA5GCKQ8jPBS b1sSQu/sXnVb6BTD1y1EN4lWLphXo/QFY19KFzVyHbKK9xa9CsLzC/5Mpf3Fs7AeUg8cSzkuHTCW 7WeivJsOGdLHT5AmY9PDPjGy0z6bhalFEM/pjPCQA+BAlnIZxFSV0ux1niV+gnzf0coKruD/dlzX C6+t6EZu9kdJRxyVfU+GOYwijo/Z6FnLFYdBlCne4ZEzk5OZ8cSC7QNm4zuNRcgRKiGg7nXFaZTx I/6scxhAq/6af00PEtBNjYtqmoKr5eemJzKNdiP7m3gSrWCqyhAo0JR3rThOyxKFbWMT2xK3KT9R mx5HiKCYjt40eTXlWiUAYdLmsJdAoPIA+QBBCmRnfEQkXp5mAyXTIBVUuAX2KYddQlACXnsZ2u9C nazM3+ZE40UYhpZLE/UxL7hrJSk60SF3F6RYOYr2 X-Report-Abuse-To: spam@antispamquarantine.host-h.net Extract a magic number, from mt7621_spi_probe(), used to declare the number of chip select lines (which co-incides with the native chip select count of 2) to a macro. Use the newly defined MT7621_NATIVE_CS_COUNT macro to instead populate both the spi_controller's max_native_cs and num_chipselect members. Declare that the spi_controller should use_gpio_descriptors if present in the device properties (such as those declared in the cs-gpio property of a "ralink,mt7621-spi" compatible device-tree node) so that the SPI core will recalculcate num_chipselect to account for the GPIO descriptors that it should have populated in the cs_gpiod array member. Remove the assignment of mt7621_spi_transfer_one_message() to the spi_controller's transfer_one_message hook. Refactor the mt7621_spi_transfer_one_message() logic into mt7621_spi_prepare_message() and mt7621_spi_transfer_one() and assign both to the spi_controller's prepare_message and transfer_one hooks respectively. Migrate the call mt7621_spi_transfer_one_message() made to mt7621_spi_flush() just before chip select deactivation, to the end of mt7621_spi_write_half_duplex() to ensure that any pending data is shifted out of MOSI before the SPI core deactivates the chip select line. As chip select activation is now taken care of by the SPI core, due to the use of the transfer_one hook instead of transfer_one_message, the calls to mt7621_spi_set_cs() from mt7621_spi_transfer_one_message() have fallen away. And although the SPI core will handle activation for GPIO chip select lines behind the scenes, it requires a callback to allow the driver to perform controller-specific operations to control its native chip select lines. Rename mt7621_spi_set_cs() to mt7621_spi_set_native_cs() and make sure that it takes into account the activation polarity of the chip select line it's acting upon, as the passed enable parameter represents the desired line level and not the desired activation state, and then assign mt7621_set_cs() to the spi_controller's set_cs hook. Signed-off-by: Justin Swartz --- Changes from v1 to v2: Mark Brown recommended using the transfer_one hook approach, so I did. drivers/spi/spi-mt7621.c | 95 +++++++++++++++++++--------------------- 1 file changed, 45 insertions(+), 50 deletions(-) -- diff --git a/drivers/spi/spi-mt7621.c b/drivers/spi/spi-mt7621.c index 4e9053d03..3770b8e09 100644 --- a/drivers/spi/spi-mt7621.c +++ b/drivers/spi/spi-mt7621.c @@ -52,6 +52,8 @@ #define MT7621_CPOL BIT(4) #define MT7621_LSB_FIRST BIT(3) +#define MT7621_NATIVE_CS_COUNT 2 + struct mt7621_spi { struct spi_controller *host; void __iomem *base; @@ -75,10 +77,11 @@ static inline void mt7621_spi_write(struct mt7621_spi *rs, u32 reg, u32 val) iowrite32(val, rs->base + reg); } -static void mt7621_spi_set_cs(struct spi_device *spi, int enable) +static void mt7621_spi_set_native_cs(struct spi_device *spi, bool enable) { struct mt7621_spi *rs = spidev_to_mt7621_spi(spi); int cs = spi_get_chipselect(spi, 0); + bool active = spi->mode & SPI_CS_HIGH ? enable : !enable; u32 polar = 0; u32 host; @@ -94,7 +97,7 @@ static void mt7621_spi_set_cs(struct spi_device *spi, int enable) rs->pending_write = 0; - if (enable) + if (active) polar = BIT(cs); mt7621_spi_write(rs, MT7621_SPI_POLAR, polar); } @@ -154,6 +157,23 @@ static inline int mt7621_spi_wait_till_ready(struct mt7621_spi *rs) return -ETIMEDOUT; } +static int mt7621_spi_prepare_message(struct spi_controller *host, + struct spi_message *m) +{ + struct mt7621_spi *rs = spi_controller_get_devdata(host); + struct spi_device *spi = m->spi; + unsigned int speed = spi->max_speed_hz; + struct spi_transfer *t = NULL; + + mt7621_spi_wait_till_ready(rs); + + list_for_each_entry(t, &m->transfers, transfer_list) + if (t->speed_hz < speed) + speed = t->speed_hz; + + return mt7621_spi_prepare(spi, speed); +} + static void mt7621_spi_read_half_duplex(struct mt7621_spi *rs, int rx_len, u8 *buf) { @@ -243,59 +263,30 @@ static void mt7621_spi_write_half_duplex(struct mt7621_spi *rs, } rs->pending_write = len; + mt7621_spi_flush(rs); } -static int mt7621_spi_transfer_one_message(struct spi_controller *host, - struct spi_message *m) +static int mt7621_spi_transfer_one(struct spi_controller *host, + struct spi_device *spi, + struct spi_transfer *t) { struct mt7621_spi *rs = spi_controller_get_devdata(host); - struct spi_device *spi = m->spi; - unsigned int speed = spi->max_speed_hz; - struct spi_transfer *t = NULL; - int status = 0; - - mt7621_spi_wait_till_ready(rs); - list_for_each_entry(t, &m->transfers, transfer_list) - if (t->speed_hz < speed) - speed = t->speed_hz; - - if (mt7621_spi_prepare(spi, speed)) { - status = -EIO; - goto msg_done; - } - - /* Assert CS */ - mt7621_spi_set_cs(spi, 1); - - m->actual_length = 0; - list_for_each_entry(t, &m->transfers, transfer_list) { - if ((t->rx_buf) && (t->tx_buf)) { - /* - * This controller will shift some extra data out - * of spi_opcode if (mosi_bit_cnt > 0) && - * (cmd_bit_cnt == 0). So the claimed full-duplex - * support is broken since we have no way to read - * the MISO value during that bit. - */ - status = -EIO; - goto msg_done; - } else if (t->rx_buf) { - mt7621_spi_read_half_duplex(rs, t->len, t->rx_buf); - } else if (t->tx_buf) { - mt7621_spi_write_half_duplex(rs, t->len, t->tx_buf); - } - m->actual_length += t->len; + if ((t->rx_buf) && (t->tx_buf)) { + /* + * This controller will shift some extra data out + * of spi_opcode if (mosi_bit_cnt > 0) && + * (cmd_bit_cnt == 0). So the claimed full-duplex + * support is broken since we have no way to read + * the MISO value during that bit. + */ + return -EIO; + } else if (t->rx_buf) { + mt7621_spi_read_half_duplex(rs, t->len, t->rx_buf); + } else if (t->tx_buf) { + mt7621_spi_write_half_duplex(rs, t->len, t->tx_buf); } - /* Flush data and deassert CS */ - mt7621_spi_flush(rs); - mt7621_spi_set_cs(spi, 0); - -msg_done: - m->status = status; - spi_finalize_current_message(host); - return 0; } @@ -353,10 +344,14 @@ static int mt7621_spi_probe(struct platform_device *pdev) host->mode_bits = SPI_LSB_FIRST; host->flags = SPI_CONTROLLER_HALF_DUPLEX; host->setup = mt7621_spi_setup; - host->transfer_one_message = mt7621_spi_transfer_one_message; + host->prepare_message = mt7621_spi_prepare_message; + host->set_cs = mt7621_spi_set_native_cs; + host->transfer_one = mt7621_spi_transfer_one; host->bits_per_word_mask = SPI_BPW_MASK(8); host->dev.of_node = pdev->dev.of_node; - host->num_chipselect = 2; + host->max_native_cs = MT7621_NATIVE_CS_COUNT; + host->num_chipselect = MT7621_NATIVE_CS_COUNT; + host->use_gpio_descriptors = true; dev_set_drvdata(&pdev->dev, host);