From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Szyprowski Subject: Re: [PATCH 3/4] tty: serial: samsung: Increase maximum baudrate Date: Fri, 21 Dec 2018 11:23:32 +0100 Message-ID: <9be9bcd6-5b8a-da40-b232-a650eaa88d38@samsung.com> References: <20181214113410.22848-1-m.szyprowski@samsung.com> <20181214113410.22848-4-m.szyprowski@samsung.com> <20181221101553.GI13248@dell> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20181221101553.GI13248@dell> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Lee Jones Cc: linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, linux-samsung-soc@vger.kernel.org, Krzysztof Kozlowski , Bartlomiej Zolnierkiewicz , Beomho Seo , Seung-Woo Kim , Sylwester Nawrocki , Greg Kroah-Hartman List-Id: linux-serial@vger.kernel.org Hi On 2018-12-21 11:15, Lee Jones wrote: > On Fri, 14 Dec 2018, Marek Szyprowski wrote: >> From: Seung-Woo Kim >> >> This driver can be used to communicate with Bluetooth chip in high-speed >> UART mode, so increase the maximum baudrate to 3Mbps. >> >> Signed-off-by: Seung-Woo Kim >> [mszyprow: rephrased commit message] >> Signed-off-by: Marek Szyprowski >> --- >> drivers/tty/serial/samsung.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c >> index 2a49b6d876b8..9fc3559f80d9 100644 >> --- a/drivers/tty/serial/samsung.c >> +++ b/drivers/tty/serial/samsung.c >> @@ -1287,7 +1287,7 @@ static void s3c24xx_serial_set_termios(struct uart_port *port, >> * Ask the core to calculate the divisor for us. >> */ >> >> - baud = uart_get_baud_rate(port, termios, old, 0, 115200*8); >> + baud = uart_get_baud_rate(port, termios, old, 0, 3000000); > Does that mean the low speed devices will stop working? It looks like > this should be dynamically configurable based on what device is > connected to it, no? The changed parameter is maximum supported rate, so this change doesn't affect any low speed device. >> quot = s3c24xx_serial_getclk(ourport, baud, &clk, &clk_sel); >> if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST) >> quot = port->custom_divisor; Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland