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[92.5.241.147]) by smtp.gmail.com with ESMTPSA id y66sm4070595wmd.14.2020.10.11.13.52.41 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Sun, 11 Oct 2020 13:52:41 -0700 (PDT) From: Sudip Mukherjee To: Alan Stern , Greg Kroah-Hartman Cc: linux-kernel@vger.kernel.org, linux-safety@lists.elisa.tech, linux-usb@vger.kernel.org, Sudip Mukherjee Subject: [PATCH] usb: host: ehci-sched: add comment about find_tt() not returning error Date: Sun, 11 Oct 2020 21:50:08 +0100 Message-Id: <20201011205008.24369-1-sudipm.mukherjee@gmail.com> X-Mailer: git-send-email 2.11.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Add a comment explaining why find_tt() will not return error even though find_tt() is checking for NULL and other errors. Signed-off-by: Sudip Mukherjee Acked-by: Alan Stern --- drivers/usb/host/ehci-sched.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c index 6dfb242f9a4b..0f85aa9b2fb1 100644 --- a/drivers/usb/host/ehci-sched.c +++ b/drivers/usb/host/ehci-sched.c @@ -244,6 +244,12 @@ static void reserve_release_intr_bandwidth(struct ehci_hcd *ehci, /* FS/LS bus bandwidth */ if (tt_usecs) { + /* + * find_tt() will not return any error here as we have + * already called find_tt() before calling this function + * and checked for any error return. The previous call + * would have created the data structure. + */ tt = find_tt(qh->ps.udev); if (sign > 0) list_add_tail(&qh->ps.ps_list, &tt->ps_list); @@ -1337,6 +1343,12 @@ static void reserve_release_iso_bandwidth(struct ehci_hcd *ehci, } } + /* + * find_tt() will not return any error here as we have + * already called find_tt() before calling this function + * and checked for any error return. The previous call + * would have created the data structure. + */ tt = find_tt(stream->ps.udev); if (sign > 0) list_add_tail(&stream->ps.ps_list, &tt->ps_list);