Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932152AbbFRMtQ (ORCPT ); Thu, 18 Jun 2015 08:49:16 -0400 Received: from mailapp01.imgtec.com ([195.59.15.196]:3210 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752950AbbFRMtK (ORCPT ); Thu, 18 Jun 2015 08:49:10 -0400 From: Sifan Naeem To: CC: , , , Sifan Naeem Subject: [PATCH] spi: img-spfi: fix support for speeds up to 1/4th input clock Date: Thu, 18 Jun 2015 13:50:54 +0100 Message-ID: <1434631854-11258-1-git-send-email-sifan.naeem@imgtec.com> X-Mailer: git-send-email 1.7.9.5 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [192.168.167.63] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1832 Lines: 48 Setting the Same Edge bit indicates to the spfi block to receive and transmit data on the same edge of the spfi clock, which in turn doubles the operating frequency of spfi. The maximum supported frequency is limited to 1/4th of the spfi input clock, but without this bit set the maximum would be 1/8th of the input clock. The current driver calculates the divisor with maximum speed at 1/4th of the input clock, this would fail if the requested frequency is higher than 1/8 of the input clock. Any requests for 1/8th of the input clock would still pass. Signed-off-by: Sifan Naeem Fixes: 8543d0e72d43 ("spi: img-spfi: Limit bit clock to 1/4th of input clock") Cc: # 3.19+ --- drivers/spi/spi-img-spfi.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/spi/spi-img-spfi.c b/drivers/spi/spi-img-spfi.c index 1eb107f..a277faf 100644 --- a/drivers/spi/spi-img-spfi.c +++ b/drivers/spi/spi-img-spfi.c @@ -40,6 +40,7 @@ #define SPFI_CONTROL_SOFT_RESET BIT(11) #define SPFI_CONTROL_SEND_DMA BIT(10) #define SPFI_CONTROL_GET_DMA BIT(9) +#define SPFI_CONTROL_SE BIT(8) #define SPFI_CONTROL_TMODE_SHIFT 5 #define SPFI_CONTROL_TMODE_MASK 0x7 #define SPFI_CONTROL_TMODE_SINGLE 0 @@ -491,6 +492,7 @@ static void img_spfi_config(struct spi_master *master, struct spi_device *spi, else if (xfer->tx_nbits == SPI_NBITS_QUAD && xfer->rx_nbits == SPI_NBITS_QUAD) val |= SPFI_CONTROL_TMODE_QUAD << SPFI_CONTROL_TMODE_SHIFT; + val |= SPFI_CONTROL_SE; spfi_writel(spfi, val, SPFI_CONTROL); } -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/